diff --git a/.prettierignore b/.prettierignore
index 5428362b5..f1835d8dc 100644
--- a/.prettierignore
+++ b/.prettierignore
@@ -7,3 +7,4 @@ app/vendor/**
 .nyc_output/**
 .vscode/**
 test/e2e/send-eth-with-private-key-test/**
+*.scss
diff --git a/.storybook/main.js b/.storybook/main.js
index 2411f2066..8b1860ee5 100644
--- a/.storybook/main.js
+++ b/.storybook/main.js
@@ -7,7 +7,7 @@ module.exports = {
   addons: [
     '@storybook/addon-knobs',
     '@storybook/addon-actions',
-    '@storybook/addon-backgrounds'
+    '@storybook/addon-backgrounds',
   ],
   webpackFinal: async (config) => {
     config.module.strictExportPresence = true
@@ -27,18 +27,29 @@ module.exports = {
           loader: 'sass-loader',
           options: {
             sourceMap: true,
+            implementation: require('sass'),
+            sassOptions: {
+              includePaths: ['ui/app/css/'],
+            },
           },
         },
       ],
     })
-    config.plugins.push(new CopyWebpackPlugin({
-      patterns: [
-        {
-          from: path.join('node_modules', '@fortawesome', 'fontawesome-free', 'webfonts'),
-          to: path.join('fonts', 'fontawesome'),
-        },
-      ],
-    }))
+    config.plugins.push(
+      new CopyWebpackPlugin({
+        patterns: [
+          {
+            from: path.join(
+              'node_modules',
+              '@fortawesome',
+              'fontawesome-free',
+              'webfonts',
+            ),
+            to: path.join('fonts', 'fontawesome'),
+          },
+        ],
+      }),
+    )
     return config
   },
 }
diff --git a/README.md b/README.md
index 83b90ae1c..545f1218c 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,8 @@
 # MetaMask Browser Extension
 
+Hey! We are hiring JavaScript Engineers! [Apply here](https://boards.greenhouse.io/consensys/jobs/2572388)!
+---
+
 You can find the latest version of MetaMask on [our official website](https://metamask.io/). For help using MetaMask, visit our [User Support Site](https://metamask.zendesk.com/hc/en-us).
 
 For [general questions](https://metamask.zendesk.com/hc/en-us/community/topics/360000682532-General), [feature requests](https://metamask.zendesk.com/hc/en-us/community/topics/360000682552-Feature-Requests-Ideas), or [developer questions](https://metamask.zendesk.com/hc/en-us/community/topics/360001751291-Developer-Questions), visit our [Community Forum](https://metamask.zendesk.com/hc/en-us/community/topics).
diff --git a/app/scripts/background.js b/app/scripts/background.js
index 1f8badfda..c63c4ade0 100644
--- a/app/scripts/background.js
+++ b/app/scripts/background.js
@@ -19,6 +19,12 @@ import extension from 'extensionizer'
 import { storeAsStream, storeTransformStream } from '@metamask/obs-store'
 import PortStream from 'extension-port-stream'
 import { captureException } from '@sentry/browser'
+
+import {
+  ENVIRONMENT_TYPE_POPUP,
+  ENVIRONMENT_TYPE_NOTIFICATION,
+  ENVIRONMENT_TYPE_FULLSCREEN,
+} from '../../shared/constants/app'
 import migrations from './migrations'
 import Migrator from './lib/migrator'
 import ExtensionPlatform from './platforms/extension'
@@ -31,12 +37,6 @@ import rawFirstTimeState from './first-time-state'
 import getFirstPreferredLangCode from './lib/get-first-preferred-lang-code'
 import getObjStructure from './lib/getObjStructure'
 import setupEnsIpfsResolver from './lib/ens-ipfs/setup'
-
-import {
-  ENVIRONMENT_TYPE_POPUP,
-  ENVIRONMENT_TYPE_NOTIFICATION,
-  ENVIRONMENT_TYPE_FULLSCREEN,
-} from './lib/enums'
 /* eslint-enable import/first */
 
 const { sentry } = global
diff --git a/app/scripts/controllers/network/contract-addresses.js b/app/scripts/constants/contracts.js
similarity index 100%
rename from app/scripts/controllers/network/contract-addresses.js
rename to app/scripts/constants/contracts.js
diff --git a/app/scripts/controllers/detect-tokens.js b/app/scripts/controllers/detect-tokens.js
index 1ad46193d..d91fdb989 100644
--- a/app/scripts/controllers/detect-tokens.js
+++ b/app/scripts/controllers/detect-tokens.js
@@ -2,12 +2,11 @@ import Web3 from 'web3'
 import contracts from '@metamask/contract-metadata'
 import { warn } from 'loglevel'
 import SINGLE_CALL_BALANCES_ABI from 'single-call-balance-checker-abi'
-import { MAINNET_CHAIN_ID } from './network/enums'
+import { MAINNET_CHAIN_ID } from '../../../shared/constants/network'
+import { SINGLE_CALL_BALANCES_ADDRESS } from '../constants/contracts'
 
 // By default, poll every 3 minutes
 const DEFAULT_INTERVAL = 180 * 1000
-const SINGLE_CALL_BALANCES_ADDRESS =
-  '0xb1f8e55c7f64d203c1400b9d8555d050f94adf39'
 
 /**
  * A controller that polls for token exchange
diff --git a/app/scripts/controllers/incoming-transactions.js b/app/scripts/controllers/incoming-transactions.js
index 58a059dd2..e1ff68895 100644
--- a/app/scripts/controllers/incoming-transactions.js
+++ b/app/scripts/controllers/incoming-transactions.js
@@ -3,7 +3,7 @@ import log from 'loglevel'
 import BN from 'bn.js'
 import createId from '../lib/random-id'
 import { bnToHex } from '../lib/util'
-import fetchWithTimeout from '../lib/fetch-with-timeout'
+import getFetchWithTimeout from '../../../shared/modules/fetch-with-timeout'
 
 import {
   TRANSACTION_CATEGORIES,
@@ -22,11 +22,9 @@ import {
   RINKEBY_CHAIN_ID,
   ROPSTEN,
   ROPSTEN_CHAIN_ID,
-} from './network/enums'
+} from '../../../shared/constants/network'
 
-const fetch = fetchWithTimeout({
-  timeout: 30000,
-})
+const fetchWithTimeout = getFetchWithTimeout(30000)
 
 /**
  * This controller is responsible for retrieving incoming transactions. Etherscan is polled once every block to check
@@ -227,7 +225,7 @@ export default class IncomingTransactionsController {
     if (fromBlock) {
       url += `&startBlock=${parseInt(fromBlock, 10)}`
     }
-    const response = await fetch(url)
+    const response = await fetchWithTimeout(url)
     const parsedResponse = await response.json()
 
     return {
diff --git a/app/scripts/controllers/metametrics.js b/app/scripts/controllers/metametrics.js
index 3ae74cbf8..2c84ee78c 100644
--- a/app/scripts/controllers/metametrics.js
+++ b/app/scripts/controllers/metametrics.js
@@ -1,7 +1,7 @@
 import { merge, omit } from 'lodash'
 import { ObservableStore } from '@metamask/obs-store'
 import { bufferToHex, sha3 } from 'ethereumjs-util'
-import { ENVIRONMENT_TYPE_BACKGROUND } from '../lib/enums'
+import { ENVIRONMENT_TYPE_BACKGROUND } from '../../../shared/constants/app'
 import {
   METAMETRICS_ANONYMOUS_ID,
   METAMETRICS_BACKGROUND_PAGE_OBJECT,
diff --git a/app/scripts/controllers/network/createInfuraClient.js b/app/scripts/controllers/network/createInfuraClient.js
index 2a26c9b75..0f37ea4ca 100644
--- a/app/scripts/controllers/network/createInfuraClient.js
+++ b/app/scripts/controllers/network/createInfuraClient.js
@@ -8,7 +8,7 @@ import providerFromMiddleware from 'eth-json-rpc-middleware/providerFromMiddlewa
 import createInfuraMiddleware from 'eth-json-rpc-infura'
 import BlockTracker from 'eth-block-tracker'
 
-import { NETWORK_TYPE_TO_ID_MAP } from './enums'
+import { NETWORK_TYPE_TO_ID_MAP } from '../../../../shared/constants/network'
 
 export default function createInfuraClient({ network, projectId }) {
   const infuraMiddleware = createInfuraMiddleware({
diff --git a/app/scripts/controllers/network/network.js b/app/scripts/controllers/network/network.js
index 9bfc0fc07..0de14fc5c 100644
--- a/app/scripts/controllers/network/network.js
+++ b/app/scripts/controllers/network/network.js
@@ -9,25 +9,25 @@ import {
   createEventEmitterProxy,
 } from 'swappable-obj-proxy'
 import EthQuery from 'eth-query'
-import createMetamaskMiddleware from './createMetamaskMiddleware'
-import createInfuraClient from './createInfuraClient'
-import createJsonRpcClient from './createJsonRpcClient'
-
 import {
   RINKEBY,
   MAINNET,
   INFURA_PROVIDER_TYPES,
+  NETWORK_TYPE_RPC,
   NETWORK_TYPE_TO_ID_MAP,
   MAINNET_CHAIN_ID,
   RINKEBY_CHAIN_ID,
-} from './enums'
+} from '../../../../shared/constants/network'
+import createMetamaskMiddleware from './createMetamaskMiddleware'
+import createInfuraClient from './createInfuraClient'
+import createJsonRpcClient from './createJsonRpcClient'
 
 const env = process.env.METAMASK_ENV
 
 let defaultProviderConfigOpts
 if (process.env.IN_TEST === 'true') {
   defaultProviderConfigOpts = {
-    type: 'rpc',
+    type: NETWORK_TYPE_RPC,
     rpcUrl: 'http://localhost:8545',
     chainId: '0x539',
     nickname: 'Localhost 8545',
@@ -161,7 +161,7 @@ export default class NetworkController extends EventEmitter {
 
   setRpcTarget(rpcUrl, chainId, ticker = 'ETH', nickname = '', rpcPrefs) {
     this.setProviderConfig({
-      type: 'rpc',
+      type: NETWORK_TYPE_RPC,
       rpcUrl,
       chainId,
       ticker,
@@ -173,8 +173,8 @@ export default class NetworkController extends EventEmitter {
   async setProviderType(type, rpcUrl = '', ticker = 'ETH', nickname = '') {
     assert.notEqual(
       type,
-      'rpc',
-      `NetworkController - cannot call "setProviderType" with type 'rpc'. use "setRpcTarget"`,
+      NETWORK_TYPE_RPC,
+      `NetworkController - cannot call "setProviderType" with type "${NETWORK_TYPE_RPC}". Use "setRpcTarget"`,
     )
     assert(
       INFURA_PROVIDER_TYPES.includes(type),
@@ -209,7 +209,7 @@ export default class NetworkController extends EventEmitter {
 
   getNetworkIdentifier() {
     const provider = this.providerStore.getState()
-    return provider.type === 'rpc' ? provider.rpcUrl : provider.type
+    return provider.type === NETWORK_TYPE_RPC ? provider.rpcUrl : provider.type
   }
 
   //
@@ -228,7 +228,7 @@ export default class NetworkController extends EventEmitter {
     if (isInfura) {
       this._configureInfuraProvider(type, this._infuraProjectId)
       // url-based rpc endpoints
-    } else if (type === 'rpc') {
+    } else if (type === NETWORK_TYPE_RPC) {
       this._configureStandardProvider(rpcUrl, chainId)
     } else {
       throw new Error(
diff --git a/app/scripts/controllers/network/util.js b/app/scripts/controllers/network/util.js
index 958a1d4dd..9c80db551 100644
--- a/app/scripts/controllers/network/util.js
+++ b/app/scripts/controllers/network/util.js
@@ -1,4 +1,4 @@
-import { NETWORK_TO_NAME_MAP } from './enums'
+import { NETWORK_TO_NAME_MAP } from '../../../../shared/constants/network'
 
 export const getNetworkDisplayName = (key) => NETWORK_TO_NAME_MAP[key]
 
diff --git a/app/scripts/controllers/permissions/enums.js b/app/scripts/controllers/permissions/enums.js
index 510fad1b3..21356804f 100644
--- a/app/scripts/controllers/permissions/enums.js
+++ b/app/scripts/controllers/permissions/enums.js
@@ -10,11 +10,6 @@ export const METADATA_STORE_KEY = 'domainMetadata'
 
 export const METADATA_CACHE_MAX_SIZE = 100
 
-export const CAVEAT_NAMES = {
-  exposedAccounts: 'exposedAccounts',
-  primaryAccountOnly: 'primaryAccountOnly',
-}
-
 export const CAVEAT_TYPES = {
   limitResponseLength: 'limitResponseLength',
   filterResponse: 'filterResponse',
diff --git a/app/scripts/controllers/permissions/index.js b/app/scripts/controllers/permissions/index.js
index c4ffd14fb..515741a7e 100644
--- a/app/scripts/controllers/permissions/index.js
+++ b/app/scripts/controllers/permissions/index.js
@@ -6,10 +6,7 @@ import { CapabilitiesController as RpcCap } from 'rpc-cap'
 import { ethErrors } from 'eth-json-rpc-errors'
 import { cloneDeep } from 'lodash'
 
-import createPermissionsMethodMiddleware from './permissionsMethodMiddleware'
-import PermissionsLogController from './permissionsLog'
-
-// Methods that do not require any permissions to use:
+import { CAVEAT_NAMES } from '../../../../shared/constants/permissions'
 import {
   APPROVAL_TYPE,
   SAFE_METHODS, // methods that do not require any permissions to use
@@ -18,11 +15,13 @@ import {
   METADATA_CACHE_MAX_SIZE,
   LOG_STORE_KEY,
   HISTORY_STORE_KEY,
-  CAVEAT_NAMES,
   NOTIFICATION_NAMES,
   CAVEAT_TYPES,
 } from './enums'
 
+import createPermissionsMethodMiddleware from './permissionsMethodMiddleware'
+import PermissionsLogController from './permissionsLog'
+
 // instanbul ignore next
 const noop = () => undefined
 
diff --git a/app/scripts/controllers/permissions/permissionsLog.js b/app/scripts/controllers/permissions/permissionsLog.js
index e1a37f0c8..28c87af6b 100644
--- a/app/scripts/controllers/permissions/permissionsLog.js
+++ b/app/scripts/controllers/permissions/permissionsLog.js
@@ -1,6 +1,6 @@
 import { cloneDeep } from 'lodash'
+import { CAVEAT_NAMES } from '../../../../shared/constants/permissions'
 import {
-  CAVEAT_NAMES,
   HISTORY_STORE_KEY,
   LOG_IGNORE_METHODS,
   LOG_LIMIT,
diff --git a/app/scripts/controllers/preferences.js b/app/scripts/controllers/preferences.js
index 7445be65b..d8ea05856 100644
--- a/app/scripts/controllers/preferences.js
+++ b/app/scripts/controllers/preferences.js
@@ -7,7 +7,7 @@ import ethers from 'ethers'
 import log from 'loglevel'
 import { isPrefixedFormattedHexString } from '../lib/util'
 import { LISTED_CONTRACT_ADDRESSES } from '../../../shared/constants/tokens'
-import { NETWORK_TYPE_TO_ID_MAP } from './network/enums'
+import { NETWORK_TYPE_TO_ID_MAP } from '../../../shared/constants/network'
 
 export default class PreferencesController {
   /**
diff --git a/app/scripts/controllers/token-rates.js b/app/scripts/controllers/token-rates.js
index 9011b1d01..031017c83 100644
--- a/app/scripts/controllers/token-rates.js
+++ b/app/scripts/controllers/token-rates.js
@@ -2,6 +2,9 @@ import { ObservableStore } from '@metamask/obs-store'
 import log from 'loglevel'
 import { normalize as normalizeAddress } from 'eth-sig-util'
 import ethUtil from 'ethereumjs-util'
+import getFetchWithTimeout from '../../../shared/modules/fetch-with-timeout'
+
+const fetchWithTimeout = getFetchWithTimeout(30000)
 
 // By default, poll every 3 minutes
 const DEFAULT_INTERVAL = 180 * 1000
@@ -34,7 +37,7 @@ export default class TokenRatesController {
     const query = `contract_addresses=${pairs}&vs_currencies=${nativeCurrency}`
     if (this._tokens.length > 0) {
       try {
-        const response = await window.fetch(
+        const response = await fetchWithTimeout(
           `https://api.coingecko.com/api/v3/simple/token_price/ethereum?${query}`,
         )
         const prices = await response.json()
diff --git a/app/scripts/lib/account-tracker.js b/app/scripts/lib/account-tracker.js
index 850c39291..6b78081f0 100644
--- a/app/scripts/lib/account-tracker.js
+++ b/app/scripts/lib/account-tracker.js
@@ -19,14 +19,14 @@ import {
   RINKEBY_CHAIN_ID,
   ROPSTEN_CHAIN_ID,
   KOVAN_CHAIN_ID,
-} from '../controllers/network/enums'
+} from '../../../shared/constants/network'
 
 import {
   SINGLE_CALL_BALANCES_ADDRESS,
   SINGLE_CALL_BALANCES_ADDRESS_RINKEBY,
   SINGLE_CALL_BALANCES_ADDRESS_ROPSTEN,
   SINGLE_CALL_BALANCES_ADDRESS_KOVAN,
-} from '../controllers/network/contract-addresses'
+} from '../constants/contracts'
 import { bnToHex } from './util'
 
 /**
diff --git a/app/scripts/lib/decrypt-message-manager.js b/app/scripts/lib/decrypt-message-manager.js
index fc8ce03ce..e84397d42 100644
--- a/app/scripts/lib/decrypt-message-manager.js
+++ b/app/scripts/lib/decrypt-message-manager.js
@@ -3,9 +3,9 @@ import { ObservableStore } from '@metamask/obs-store'
 import ethUtil from 'ethereumjs-util'
 import { ethErrors } from 'eth-json-rpc-errors'
 import log from 'loglevel'
+import { MESSAGE_TYPE } from '../../../shared/constants/app'
 import { addHexPrefix } from './util'
 import createId from './random-id'
-import { MESSAGE_TYPE } from './enums'
 
 const hexRe = /^[0-9A-Fa-f]+$/gu
 
diff --git a/app/scripts/lib/encryption-public-key-manager.js b/app/scripts/lib/encryption-public-key-manager.js
index d563cae0b..48f2ab701 100644
--- a/app/scripts/lib/encryption-public-key-manager.js
+++ b/app/scripts/lib/encryption-public-key-manager.js
@@ -2,8 +2,8 @@ import EventEmitter from 'events'
 import { ObservableStore } from '@metamask/obs-store'
 import { ethErrors } from 'eth-json-rpc-errors'
 import log from 'loglevel'
+import { MESSAGE_TYPE } from '../../../shared/constants/app'
 import createId from './random-id'
-import { MESSAGE_TYPE } from './enums'
 
 /**
  * Represents, and contains data about, an 'eth_getEncryptionPublicKey' type request. These are created when
diff --git a/app/scripts/lib/ens-ipfs/setup.js b/app/scripts/lib/ens-ipfs/setup.js
index ab4cec023..9ec6e1492 100644
--- a/app/scripts/lib/ens-ipfs/setup.js
+++ b/app/scripts/lib/ens-ipfs/setup.js
@@ -1,6 +1,9 @@
 import extension from 'extensionizer'
+import getFetchWithTimeout from '../../../../shared/modules/fetch-with-timeout'
 import resolveEnsToIpfsContentId from './resolver'
 
+const fetchWithTimeout = getFetchWithTimeout(30000)
+
 const supportedTopLevelDomains = ['eth']
 
 export default function setupEnsIpfsResolver({
@@ -55,7 +58,9 @@ export default function setupEnsIpfsResolver({
         )}.${ipfsGateway}${pathname}${search || ''}${fragment || ''}`
         try {
           // check if ipfs gateway has result
-          const response = await window.fetch(resolvedUrl, { method: 'HEAD' })
+          const response = await fetchWithTimeout(resolvedUrl, {
+            method: 'HEAD',
+          })
           if (response.status === 200) {
             url = resolvedUrl
           }
diff --git a/app/scripts/lib/message-manager.js b/app/scripts/lib/message-manager.js
index 872f97b0d..a3f0dee58 100644
--- a/app/scripts/lib/message-manager.js
+++ b/app/scripts/lib/message-manager.js
@@ -2,8 +2,8 @@ import EventEmitter from 'events'
 import { ObservableStore } from '@metamask/obs-store'
 import ethUtil from 'ethereumjs-util'
 import { ethErrors } from 'eth-json-rpc-errors'
+import { MESSAGE_TYPE } from '../../../shared/constants/app'
 import createId from './random-id'
-import { MESSAGE_TYPE } from './enums'
 
 /**
  * Represents, and contains data about, an 'eth_sign' type signature request. These are created when a signature for
diff --git a/app/scripts/lib/network-store.js b/app/scripts/lib/network-store.js
index cc2898292..bfa7a8ba4 100644
--- a/app/scripts/lib/network-store.js
+++ b/app/scripts/lib/network-store.js
@@ -1,4 +1,7 @@
 import log from 'loglevel'
+import getFetchWithTimeout from '../../../shared/modules/fetch-with-timeout'
+
+const fetchWithTimeout = getFetchWithTimeout(30000)
 
 const FIXTURE_SERVER_HOST = 'localhost'
 const FIXTURE_SERVER_PORT = 12345
@@ -24,7 +27,7 @@ export default class ReadOnlyNetworkStore {
    */
   async _init() {
     try {
-      const response = await window.fetch(FIXTURE_SERVER_URL)
+      const response = await fetchWithTimeout(FIXTURE_SERVER_URL)
       if (response.ok) {
         this._state = await response.json()
       }
diff --git a/app/scripts/lib/personal-message-manager.js b/app/scripts/lib/personal-message-manager.js
index 52d20588f..c08dddbb2 100644
--- a/app/scripts/lib/personal-message-manager.js
+++ b/app/scripts/lib/personal-message-manager.js
@@ -3,9 +3,9 @@ import { ObservableStore } from '@metamask/obs-store'
 import ethUtil from 'ethereumjs-util'
 import { ethErrors } from 'eth-json-rpc-errors'
 import log from 'loglevel'
+import { MESSAGE_TYPE } from '../../../shared/constants/app'
 import { addHexPrefix } from './util'
 import createId from './random-id'
-import { MESSAGE_TYPE } from './enums'
 
 const hexRe = /^[0-9A-Fa-f]+$/gu
 
diff --git a/app/scripts/lib/rpc-method-middleware/handlers/get-provider-state.js b/app/scripts/lib/rpc-method-middleware/handlers/get-provider-state.js
index 32b3c18c6..760517e10 100644
--- a/app/scripts/lib/rpc-method-middleware/handlers/get-provider-state.js
+++ b/app/scripts/lib/rpc-method-middleware/handlers/get-provider-state.js
@@ -1,4 +1,4 @@
-import { MESSAGE_TYPE } from '../../enums'
+import { MESSAGE_TYPE } from '../../../../../shared/constants/app'
 
 /**
  * This RPC method gets background state relevant to the provider.
diff --git a/app/scripts/lib/rpc-method-middleware/handlers/log-web3-shim-usage.js b/app/scripts/lib/rpc-method-middleware/handlers/log-web3-shim-usage.js
index 21e908000..3fb5a5743 100644
--- a/app/scripts/lib/rpc-method-middleware/handlers/log-web3-shim-usage.js
+++ b/app/scripts/lib/rpc-method-middleware/handlers/log-web3-shim-usage.js
@@ -1,4 +1,4 @@
-import { MESSAGE_TYPE } from '../../enums'
+import { MESSAGE_TYPE } from '../../../../../shared/constants/app'
 
 /**
  * This RPC method is called by the inpage provider whenever it detects the
diff --git a/app/scripts/lib/rpc-method-middleware/handlers/watch-asset.js b/app/scripts/lib/rpc-method-middleware/handlers/watch-asset.js
index 1c5f4c1db..60c8ad6da 100644
--- a/app/scripts/lib/rpc-method-middleware/handlers/watch-asset.js
+++ b/app/scripts/lib/rpc-method-middleware/handlers/watch-asset.js
@@ -1,4 +1,4 @@
-import { MESSAGE_TYPE } from '../../enums'
+import { MESSAGE_TYPE } from '../../../../../shared/constants/app'
 
 const watchAsset = {
   methodNames: [MESSAGE_TYPE.WATCH_ASSET, MESSAGE_TYPE.WATCH_ASSET_LEGACY],
diff --git a/app/scripts/lib/typed-message-manager.js b/app/scripts/lib/typed-message-manager.js
index 6bcfe846b..1dce10bc8 100644
--- a/app/scripts/lib/typed-message-manager.js
+++ b/app/scripts/lib/typed-message-manager.js
@@ -6,8 +6,8 @@ import { typedSignatureHash, TYPED_MESSAGE_SCHEMA } from 'eth-sig-util'
 import { isValidAddress } from 'ethereumjs-util'
 import log from 'loglevel'
 import jsonschema from 'jsonschema'
+import { MESSAGE_TYPE } from '../../../shared/constants/app'
 import createId from './random-id'
-import { MESSAGE_TYPE } from './enums'
 
 /**
  * Represents, and contains data about, an 'eth_signTypedData' type signature request. These are created when a
diff --git a/app/scripts/lib/util.js b/app/scripts/lib/util.js
index 1816d04ab..6750d8b43 100644
--- a/app/scripts/lib/util.js
+++ b/app/scripts/lib/util.js
@@ -14,7 +14,7 @@ import {
   PLATFORM_CHROME,
   PLATFORM_EDGE,
   PLATFORM_BRAVE,
-} from './enums'
+} from '../../../shared/constants/app'
 
 /**
  * @see {@link getEnvironmentType}
diff --git a/app/scripts/migrations/051.js b/app/scripts/migrations/051.js
index 0128dd656..4c024458d 100644
--- a/app/scripts/migrations/051.js
+++ b/app/scripts/migrations/051.js
@@ -1,5 +1,5 @@
 import { cloneDeep } from 'lodash'
-import { NETWORK_TYPE_TO_ID_MAP } from '../controllers/network/enums'
+import { NETWORK_TYPE_TO_ID_MAP } from '../../../shared/constants/network'
 
 const version = 51
 
diff --git a/app/scripts/platforms/extension.js b/app/scripts/platforms/extension.js
index 3644e02cb..88117700d 100644
--- a/app/scripts/platforms/extension.js
+++ b/app/scripts/platforms/extension.js
@@ -1,7 +1,7 @@
 import extension from 'extensionizer'
 import { createExplorerLink as explorerLink } from '@metamask/etherscan-link'
 import { getEnvironmentType, checkForError } from '../lib/util'
-import { ENVIRONMENT_TYPE_BACKGROUND } from '../lib/enums'
+import { ENVIRONMENT_TYPE_BACKGROUND } from '../../../shared/constants/app'
 import { TRANSACTION_STATUSES } from '../../../shared/constants/transaction'
 
 export default class ExtensionPlatform {
diff --git a/app/scripts/ui.js b/app/scripts/ui.js
index f1f4a7b78..7aca1b724 100644
--- a/app/scripts/ui.js
+++ b/app/scripts/ui.js
@@ -12,12 +12,12 @@ import EthQuery from 'eth-query'
 import StreamProvider from 'web3-stream-provider'
 import log from 'loglevel'
 import launchMetaMaskUi from '../../ui'
-import ExtensionPlatform from './platforms/extension'
-import { setupMultiplex } from './lib/stream-utils'
 import {
   ENVIRONMENT_TYPE_FULLSCREEN,
   ENVIRONMENT_TYPE_POPUP,
-} from './lib/enums'
+} from '../../shared/constants/app'
+import ExtensionPlatform from './platforms/extension'
+import { setupMultiplex } from './lib/stream-utils'
 import { getEnvironmentType } from './lib/util'
 
 start().catch(log.error)
diff --git a/development/build/styles.js b/development/build/styles.js
index 966b2c818..c8b9e6718 100644
--- a/development/build/styles.js
+++ b/development/build/styles.js
@@ -1,7 +1,7 @@
 const pify = require('pify')
 const gulp = require('gulp')
 const sass = require('gulp-sass')
-sass.compiler = require('node-sass')
+sass.compiler = require('sass')
 const autoprefixer = require('gulp-autoprefixer')
 const gulpStylelint = require('gulp-stylelint')
 const watch = require('gulp-watch')
diff --git a/package.json b/package.json
index 58b75ae66..131f0f506 100644
--- a/package.json
+++ b/package.json
@@ -246,7 +246,7 @@
     "gulp-rename": "^2.0.0",
     "gulp-replace": "^1.0.0",
     "gulp-rtlcss": "^1.4.0",
-    "gulp-sass": "^4.0.0",
+    "gulp-sass": "^4.1.0",
     "gulp-sourcemaps": "^2.6.0",
     "gulp-stylelint": "^13.0.0",
     "gulp-terser-js": "^5.2.2",
@@ -259,7 +259,6 @@
     "mocha": "^7.2.0",
     "nock": "^9.0.14",
     "node-fetch": "^2.6.1",
-    "node-sass": "^4.14.1",
     "nyc": "^15.0.0",
     "polyfill-crypto.getrandomvalues": "^1.0.0",
     "prettier": "^2.1.1",
@@ -275,7 +274,8 @@
     "remote-redux-devtools": "^0.5.16",
     "remotedev-server": "^0.3.1",
     "resolve-url-loader": "^3.1.2",
-    "sass-loader": "^7.0.1",
+    "sass": "^1.32.4",
+    "sass-loader": "^10.1.1",
     "selenium-webdriver": "4.0.0-alpha.7",
     "serve-handler": "^6.1.2",
     "ses": "0.11.0",
diff --git a/app/scripts/lib/enums.js b/shared/constants/app.js
similarity index 59%
rename from app/scripts/lib/enums.js
rename to shared/constants/app.js
index a6b7a99de..90e4726b0 100644
--- a/app/scripts/lib/enums.js
+++ b/shared/constants/app.js
@@ -6,19 +6,18 @@
  * background - The background process that powers the extension
  * @typedef {'popup' | 'notification' | 'fullscreen' | 'background'} EnvironmentType
  */
+export const ENVIRONMENT_TYPE_POPUP = 'popup'
+export const ENVIRONMENT_TYPE_NOTIFICATION = 'notification'
+export const ENVIRONMENT_TYPE_FULLSCREEN = 'fullscreen'
+export const ENVIRONMENT_TYPE_BACKGROUND = 'background'
 
-const ENVIRONMENT_TYPE_POPUP = 'popup'
-const ENVIRONMENT_TYPE_NOTIFICATION = 'notification'
-const ENVIRONMENT_TYPE_FULLSCREEN = 'fullscreen'
-const ENVIRONMENT_TYPE_BACKGROUND = 'background'
+export const PLATFORM_BRAVE = 'Brave'
+export const PLATFORM_CHROME = 'Chrome'
+export const PLATFORM_EDGE = 'Edge'
+export const PLATFORM_FIREFOX = 'Firefox'
+export const PLATFORM_OPERA = 'Opera'
 
-const PLATFORM_BRAVE = 'Brave'
-const PLATFORM_CHROME = 'Chrome'
-const PLATFORM_EDGE = 'Edge'
-const PLATFORM_FIREFOX = 'Firefox'
-const PLATFORM_OPERA = 'Opera'
-
-const MESSAGE_TYPE = {
+export const MESSAGE_TYPE = {
   ETH_DECRYPT: 'eth_decrypt',
   ETH_GET_ENCRYPTION_PUBLIC_KEY: 'eth_getEncryptionPublicKey',
   ETH_SIGN: 'eth_sign',
@@ -29,16 +28,3 @@ const MESSAGE_TYPE = {
   WATCH_ASSET: 'wallet_watchAsset',
   WATCH_ASSET_LEGACY: 'metamask_watchAsset',
 }
-
-export {
-  ENVIRONMENT_TYPE_POPUP,
-  ENVIRONMENT_TYPE_NOTIFICATION,
-  ENVIRONMENT_TYPE_FULLSCREEN,
-  ENVIRONMENT_TYPE_BACKGROUND,
-  MESSAGE_TYPE,
-  PLATFORM_BRAVE,
-  PLATFORM_CHROME,
-  PLATFORM_EDGE,
-  PLATFORM_FIREFOX,
-  PLATFORM_OPERA,
-}
diff --git a/shared/constants/metametrics.js b/shared/constants/metametrics.js
index 7bd2c4c5e..edb37a2a1 100644
--- a/shared/constants/metametrics.js
+++ b/shared/constants/metametrics.js
@@ -1,6 +1,6 @@
 // Type Imports
 /**
- * @typedef {import('../../app/scripts/lib/enums').EnvironmentType} EnvironmentType
+ * @typedef {import('../../shared/constants/app').EnvironmentType} EnvironmentType
  */
 
 // Type Declarations
diff --git a/app/scripts/controllers/network/enums.js b/shared/constants/network.js
similarity index 98%
rename from app/scripts/controllers/network/enums.js
rename to shared/constants/network.js
index 6887a08dd..eba397466 100644
--- a/app/scripts/controllers/network/enums.js
+++ b/shared/constants/network.js
@@ -3,6 +3,7 @@ export const RINKEBY = 'rinkeby'
 export const KOVAN = 'kovan'
 export const MAINNET = 'mainnet'
 export const GOERLI = 'goerli'
+export const NETWORK_TYPE_RPC = 'rpc'
 
 export const MAINNET_NETWORK_ID = '1'
 export const ROPSTEN_NETWORK_ID = '3'
diff --git a/shared/constants/permissions.js b/shared/constants/permissions.js
new file mode 100644
index 000000000..f396fbeba
--- /dev/null
+++ b/shared/constants/permissions.js
@@ -0,0 +1,4 @@
+export const CAVEAT_NAMES = {
+  exposedAccounts: 'exposedAccounts',
+  primaryAccountOnly: 'primaryAccountOnly',
+}
diff --git a/app/scripts/lib/fetch-with-timeout.js b/shared/modules/fetch-with-timeout.js
similarity index 64%
rename from app/scripts/lib/fetch-with-timeout.js
rename to shared/modules/fetch-with-timeout.js
index a9e895b12..e97ae3402 100644
--- a/app/scripts/lib/fetch-with-timeout.js
+++ b/shared/modules/fetch-with-timeout.js
@@ -1,4 +1,10 @@
-const fetchWithTimeout = ({ timeout = 120000 } = {}) => {
+import { memoize } from 'lodash'
+
+const getFetchWithTimeout = memoize((timeout) => {
+  if (!Number.isInteger(timeout) || timeout < 1) {
+    throw new Error('Must specify positive integer timeout.')
+  }
+
   return async function _fetch(url, opts) {
     const abortController = new window.AbortController()
     const { signal } = abortController
@@ -18,6 +24,6 @@ const fetchWithTimeout = ({ timeout = 120000 } = {}) => {
       throw e
     }
   }
-}
+})
 
-export default fetchWithTimeout
+export default getFetchWithTimeout
diff --git a/test/unit/actions/config_test.js b/test/unit/actions/config_test.js
index ed60ac299..35064ad9c 100644
--- a/test/unit/actions/config_test.js
+++ b/test/unit/actions/config_test.js
@@ -2,6 +2,7 @@ import assert from 'assert'
 import freeze from 'deep-freeze-strict'
 import reducers from '../../../ui/app/ducks'
 import * as actionConstants from '../../../ui/app/store/actionConstants'
+import { NETWORK_TYPE_RPC } from '../../../shared/constants/network'
 
 describe('config view actions', function () {
   const initialState = {
@@ -25,7 +26,7 @@ describe('config view actions', function () {
       }
 
       const result = reducers(initialState, action)
-      assert.equal(result.metamask.provider.type, 'rpc')
+      assert.equal(result.metamask.provider.type, NETWORK_TYPE_RPC)
       assert.equal(result.metamask.provider.rpcUrl, 'foo')
     })
   })
diff --git a/test/unit/app/controllers/detect-tokens-test.js b/test/unit/app/controllers/detect-tokens-test.js
index 6039a943c..d76906d26 100644
--- a/test/unit/app/controllers/detect-tokens-test.js
+++ b/test/unit/app/controllers/detect-tokens-test.js
@@ -7,10 +7,7 @@ import BigNumber from 'bignumber.js'
 import DetectTokensController from '../../../../app/scripts/controllers/detect-tokens'
 import NetworkController from '../../../../app/scripts/controllers/network/network'
 import PreferencesController from '../../../../app/scripts/controllers/preferences'
-import {
-  MAINNET,
-  ROPSTEN,
-} from '../../../../app/scripts/controllers/network/enums'
+import { MAINNET, ROPSTEN } from '../../../../shared/constants/network'
 
 describe('DetectTokensController', function () {
   const sandbox = sinon.createSandbox()
diff --git a/test/unit/app/controllers/incoming-transactions-test.js b/test/unit/app/controllers/incoming-transactions-test.js
index 61768cee8..af8ac1084 100644
--- a/test/unit/app/controllers/incoming-transactions-test.js
+++ b/test/unit/app/controllers/incoming-transactions-test.js
@@ -14,7 +14,7 @@ import {
   ROPSTEN,
   ROPSTEN_CHAIN_ID,
   ROPSTEN_NETWORK_ID,
-} from '../../../../app/scripts/controllers/network/enums'
+} from '../../../../shared/constants/network'
 import {
   TRANSACTION_CATEGORIES,
   TRANSACTION_STATUSES,
diff --git a/test/unit/app/controllers/metametrics-test.js b/test/unit/app/controllers/metametrics-test.js
index 4e66fec4a..11c012bfc 100644
--- a/test/unit/app/controllers/metametrics-test.js
+++ b/test/unit/app/controllers/metametrics-test.js
@@ -1,7 +1,7 @@
 import { strict as assert } from 'assert'
 import sinon from 'sinon'
 import MetaMetricsController from '../../../../app/scripts/controllers/metametrics'
-import { ENVIRONMENT_TYPE_BACKGROUND } from '../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_BACKGROUND } from '../../../../shared/constants/app'
 import { createSegmentMock } from '../../../../app/scripts/lib/segment'
 import {
   METAMETRICS_ANONYMOUS_ID,
diff --git a/test/unit/app/controllers/permissions/mocks.js b/test/unit/app/controllers/permissions/mocks.js
index 48937faf2..8d7d75e75 100644
--- a/test/unit/app/controllers/permissions/mocks.js
+++ b/test/unit/app/controllers/permissions/mocks.js
@@ -5,8 +5,8 @@ import { ApprovalController } from '@metamask/controllers'
 
 import _getRestrictedMethods from '../../../../../app/scripts/controllers/permissions/restrictedMethods'
 
+import { CAVEAT_NAMES } from '../../../../../shared/constants/permissions'
 import {
-  CAVEAT_NAMES,
   CAVEAT_TYPES,
   NOTIFICATION_NAMES,
 } from '../../../../../app/scripts/controllers/permissions/enums'
diff --git a/test/unit/app/controllers/swaps-test.js b/test/unit/app/controllers/swaps-test.js
index 38f948088..2622d04eb 100644
--- a/test/unit/app/controllers/swaps-test.js
+++ b/test/unit/app/controllers/swaps-test.js
@@ -8,7 +8,7 @@ import { ObservableStore } from '@metamask/obs-store'
 import {
   ROPSTEN_NETWORK_ID,
   MAINNET_NETWORK_ID,
-} from '../../../../app/scripts/controllers/network/enums'
+} from '../../../../shared/constants/network'
 import { ETH_SWAPS_TOKEN_ADDRESS } from '../../../../ui/app/helpers/constants/swaps'
 import { createTestProviderTools } from '../../../stub/provider'
 import SwapsController, {
diff --git a/test/unit/app/fetch-with-timeout.test.js b/test/unit/app/fetch-with-timeout.test.js
index 89ea2fec9..dd91ff58b 100644
--- a/test/unit/app/fetch-with-timeout.test.js
+++ b/test/unit/app/fetch-with-timeout.test.js
@@ -1,14 +1,16 @@
 import assert from 'assert'
 import nock from 'nock'
 
-import fetchWithTimeout from '../../../app/scripts/lib/fetch-with-timeout'
+import getFetchWithTimeout from '../../../shared/modules/fetch-with-timeout'
 
-describe('fetchWithTimeout', function () {
+describe('getFetchWithTimeout', function () {
   it('fetches a url', async function () {
     nock('https://api.infura.io').get('/money').reply(200, '{"hodl": false}')
 
-    const fetch = fetchWithTimeout()
-    const response = await (await fetch('https://api.infura.io/money')).json()
+    const fetchWithTimeout = getFetchWithTimeout(30000)
+    const response = await (
+      await fetchWithTimeout('https://api.infura.io/money')
+    ).json()
     assert.deepEqual(response, {
       hodl: false,
     })
@@ -20,12 +22,10 @@ describe('fetchWithTimeout', function () {
       .delay(2000)
       .reply(200, '{"moon": "2012-12-21T11:11:11Z"}')
 
-    const fetch = fetchWithTimeout({
-      timeout: 123,
-    })
+    const fetchWithTimeout = getFetchWithTimeout(123)
 
     try {
-      await fetch('https://api.infura.io/moon').then((r) => r.json())
+      await fetchWithTimeout('https://api.infura.io/moon').then((r) => r.json())
       assert.fail('Request should throw')
     } catch (e) {
       assert.ok(e)
@@ -38,15 +38,20 @@ describe('fetchWithTimeout', function () {
       .delay(2000)
       .reply(200, '{"moon": "2012-12-21T11:11:11Z"}')
 
-    const fetch = fetchWithTimeout({
-      timeout: 123,
-    })
+    const fetchWithTimeout = getFetchWithTimeout(123)
 
     try {
-      await fetch('https://api.infura.io/moon').then((r) => r.json())
+      await fetchWithTimeout('https://api.infura.io/moon').then((r) => r.json())
       assert.fail('Request should be aborted')
     } catch (e) {
       assert.deepEqual(e.message, 'Aborted')
     }
   })
+
+  it('throws on invalid timeout', async function () {
+    assert.throws(() => getFetchWithTimeout(), 'should throw')
+    assert.throws(() => getFetchWithTimeout(-1), 'should throw')
+    assert.throws(() => getFetchWithTimeout({}), 'should throw')
+    assert.throws(() => getFetchWithTimeout(true), 'should throw')
+  })
 })
diff --git a/test/unit/app/util-test.js b/test/unit/app/util-test.js
index f2372576f..802ae93c9 100644
--- a/test/unit/app/util-test.js
+++ b/test/unit/app/util-test.js
@@ -10,7 +10,7 @@ import {
   ENVIRONMENT_TYPE_NOTIFICATION,
   ENVIRONMENT_TYPE_FULLSCREEN,
   ENVIRONMENT_TYPE_BACKGROUND,
-} from '../../../app/scripts/lib/enums'
+} from '../../../shared/constants/app'
 
 describe('app utils', function () {
   describe('getEnvironmentType', function () {
diff --git a/test/unit/localhostState.js b/test/unit/localhostState.js
index 8b0c68507..069ac0b78 100644
--- a/test/unit/localhostState.js
+++ b/test/unit/localhostState.js
@@ -1,3 +1,5 @@
+import { NETWORK_TYPE_RPC } from '../../shared/constants/network'
+
 /**
  * @typedef {Object} FirstTimeState
  * @property {Object} config Initial configuration parameters
@@ -11,7 +13,7 @@ const initialState = {
   config: {},
   NetworkController: {
     provider: {
-      type: 'rpc',
+      type: NETWORK_TYPE_RPC,
       rpcUrl: 'http://localhost:8545',
       chainId: '0x539',
     },
diff --git a/test/unit/migrations/051-test.js b/test/unit/migrations/051-test.js
index d692e5773..ae0a78afe 100644
--- a/test/unit/migrations/051-test.js
+++ b/test/unit/migrations/051-test.js
@@ -3,7 +3,7 @@ import migration51 from '../../../app/scripts/migrations/051'
 import {
   INFURA_PROVIDER_TYPES,
   NETWORK_TYPE_TO_ID_MAP,
-} from '../../../app/scripts/controllers/network/enums'
+} from '../../../shared/constants/network'
 
 describe('migration #51', function () {
   it('should update the version metadata', async function () {
diff --git a/ui/app/components/app/account-menu/account-menu.component.js b/ui/app/components/app/account-menu/account-menu.component.js
index 00c889a94..f16cb41a4 100644
--- a/ui/app/components/app/account-menu/account-menu.component.js
+++ b/ui/app/components/app/account-menu/account-menu.component.js
@@ -4,7 +4,7 @@ import { debounce } from 'lodash'
 import Fuse from 'fuse.js'
 import InputAdornment from '@material-ui/core/InputAdornment'
 import classnames from 'classnames'
-import { ENVIRONMENT_TYPE_POPUP } from '../../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_POPUP } from '../../../../../shared/constants/app'
 import { getEnvironmentType } from '../../../../../app/scripts/lib/util'
 import Identicon from '../../ui/identicon'
 import SiteIcon from '../../ui/site-icon'
diff --git a/ui/app/components/app/confirm-page-container/confirm-page-container-header/confirm-page-container-header.component.js b/ui/app/components/app/confirm-page-container/confirm-page-container-header/confirm-page-container-header.component.js
index 72e741a6b..bdc6295d6 100644
--- a/ui/app/components/app/confirm-page-container/confirm-page-container-header/confirm-page-container-header.component.js
+++ b/ui/app/components/app/confirm-page-container/confirm-page-container-header/confirm-page-container-header.component.js
@@ -3,7 +3,7 @@ import PropTypes from 'prop-types'
 import {
   ENVIRONMENT_TYPE_POPUP,
   ENVIRONMENT_TYPE_NOTIFICATION,
-} from '../../../../../../app/scripts/lib/enums'
+} from '../../../../../../shared/constants/app'
 import { getEnvironmentType } from '../../../../../../app/scripts/lib/util'
 import NetworkDisplay from '../../network-display'
 import Identicon from '../../../ui/identicon'
diff --git a/ui/app/components/app/dropdowns/network-dropdown.js b/ui/app/components/app/dropdowns/network-dropdown.js
index e55f77afc..daf1048bb 100644
--- a/ui/app/components/app/dropdowns/network-dropdown.js
+++ b/ui/app/components/app/dropdowns/network-dropdown.js
@@ -9,7 +9,8 @@ import {
   NETWORKS_ROUTE,
   NETWORKS_FORM_ROUTE,
 } from '../../../helpers/constants/routes'
-import { ENVIRONMENT_TYPE_FULLSCREEN } from '../../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_FULLSCREEN } from '../../../../../shared/constants/app'
+import { NETWORK_TYPE_RPC } from '../../../../../shared/constants/network'
 import {
   getEnvironmentType,
   isPrefixedFormattedHexString,
@@ -117,7 +118,7 @@ class NetworkDropdown extends Component {
     return reversedRpcListDetail.map((entry) => {
       const { rpcUrl, chainId, ticker = 'ETH', nickname = '' } = entry
       const isCurrentRpcTarget =
-        provider.type === 'rpc' && rpcUrl === provider.rpcUrl
+        provider.type === NETWORK_TYPE_RPC && rpcUrl === provider.rpcUrl
 
       return (
         <DropdownMenuItem
diff --git a/ui/app/components/app/loading-network-screen/loading-network-screen.container.js b/ui/app/components/app/loading-network-screen/loading-network-screen.container.js
index 59a97a3cc..9dbb96b85 100644
--- a/ui/app/components/app/loading-network-screen/loading-network-screen.container.js
+++ b/ui/app/components/app/loading-network-screen/loading-network-screen.container.js
@@ -1,4 +1,5 @@
 import { connect } from 'react-redux'
+import { NETWORK_TYPE_RPC } from '../../../../../shared/constants/network'
 import * as actions from '../../../store/actions'
 import { getNetworkIdentifier } from '../../../selectors'
 import LoadingNetworkScreen from './loading-network-screen.component'
@@ -9,7 +10,9 @@ const mapStateToProps = (state) => {
   const { rpcUrl, chainId, ticker, nickname, type } = provider
 
   const setProviderArgs =
-    type === 'rpc' ? [rpcUrl, chainId, ticker, nickname] : [provider.type]
+    type === NETWORK_TYPE_RPC
+      ? [rpcUrl, chainId, ticker, nickname]
+      : [provider.type]
 
   return {
     isLoadingNetwork: network === 'loading',
diff --git a/ui/app/components/app/menu-bar/account-options-menu.js b/ui/app/components/app/menu-bar/account-options-menu.js
index 60ca1c598..d3c9723e7 100644
--- a/ui/app/components/app/menu-bar/account-options-menu.js
+++ b/ui/app/components/app/menu-bar/account-options-menu.js
@@ -16,7 +16,7 @@ import {
 import { useI18nContext } from '../../../hooks/useI18nContext'
 import { useMetricEvent } from '../../../hooks/useMetricEvent'
 import { getEnvironmentType } from '../../../../../app/scripts/lib/util'
-import { ENVIRONMENT_TYPE_FULLSCREEN } from '../../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_FULLSCREEN } from '../../../../../shared/constants/app'
 
 export default function AccountOptionsMenu({ anchorElement, onClose }) {
   const t = useI18nContext()
diff --git a/ui/app/components/app/menu-bar/menu-bar.js b/ui/app/components/app/menu-bar/menu-bar.js
index d9d13fcb1..f6c70a43e 100644
--- a/ui/app/components/app/menu-bar/menu-bar.js
+++ b/ui/app/components/app/menu-bar/menu-bar.js
@@ -5,7 +5,7 @@ import { useSelector } from 'react-redux'
 import SelectedAccount from '../selected-account'
 import ConnectedStatusIndicator from '../connected-status-indicator'
 import { getEnvironmentType } from '../../../../../app/scripts/lib/util'
-import { ENVIRONMENT_TYPE_POPUP } from '../../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_POPUP } from '../../../../../shared/constants/app'
 import { CONNECTED_ACCOUNTS_ROUTE } from '../../../helpers/constants/routes'
 import { useI18nContext } from '../../../hooks/useI18nContext'
 import { useMetricEvent } from '../../../hooks/useMetricEvent'
diff --git a/ui/app/components/app/modals/modal.js b/ui/app/components/app/modals/modal.js
index 46f915b16..5ad7d3470 100644
--- a/ui/app/components/app/modals/modal.js
+++ b/ui/app/components/app/modals/modal.js
@@ -6,7 +6,7 @@ import * as actions from '../../../store/actions'
 import { resetCustomData as resetCustomGasData } from '../../../ducks/gas/gas.duck'
 import isMobileView from '../../../../lib/is-mobile-view'
 import { getEnvironmentType } from '../../../../../app/scripts/lib/util'
-import { ENVIRONMENT_TYPE_POPUP } from '../../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_POPUP } from '../../../../../shared/constants/app'
 
 // Modal Components
 import ConfirmCustomizeGasModal from '../gas-customization/gas-modal-page-container'
diff --git a/ui/app/components/app/modals/qr-scanner/qr-scanner.component.js b/ui/app/components/app/modals/qr-scanner/qr-scanner.component.js
index 54556f630..2f82ce65f 100644
--- a/ui/app/components/app/modals/qr-scanner/qr-scanner.component.js
+++ b/ui/app/components/app/modals/qr-scanner/qr-scanner.component.js
@@ -3,7 +3,7 @@ import PropTypes from 'prop-types'
 import log from 'loglevel'
 import { BrowserQRCodeReader } from '@zxing/library'
 import { getEnvironmentType } from '../../../../../../app/scripts/lib/util'
-import { ENVIRONMENT_TYPE_FULLSCREEN } from '../../../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_FULLSCREEN } from '../../../../../../shared/constants/app'
 import Spinner from '../../../ui/spinner'
 import WebcamUtils from '../../../../../lib/webcam-utils'
 import PageContainerFooter from '../../../ui/page-container/page-container-footer/page-container-footer.component'
diff --git a/ui/app/components/app/network-display/network-display.component.js b/ui/app/components/app/network-display/network-display.component.js
index 0838ddc57..c045c1527 100644
--- a/ui/app/components/app/network-display/network-display.component.js
+++ b/ui/app/components/app/network-display/network-display.component.js
@@ -1,21 +1,7 @@
 import React, { Component } from 'react'
 import PropTypes from 'prop-types'
 import classnames from 'classnames'
-import {
-  MAINNET_NETWORK_ID,
-  ROPSTEN_NETWORK_ID,
-  RINKEBY_NETWORK_ID,
-  KOVAN_NETWORK_ID,
-  GOERLI_NETWORK_ID,
-} from '../../../../../app/scripts/controllers/network/enums'
-
-const networkIdToTypeMap = {
-  [MAINNET_NETWORK_ID]: 'mainnet',
-  [ROPSTEN_NETWORK_ID]: 'ropsten',
-  [RINKEBY_NETWORK_ID]: 'rinkeby',
-  [GOERLI_NETWORK_ID]: 'goerli',
-  [KOVAN_NETWORK_ID]: 'kovan',
-}
+import { NETWORK_TYPE_RPC } from '../../../../../shared/constants/network'
 
 export default class NetworkDisplay extends Component {
   static defaultProps = {
@@ -23,9 +9,9 @@ export default class NetworkDisplay extends Component {
   }
 
   static propTypes = {
+    networkNickname: PropTypes.string.isRequired,
+    networkType: PropTypes.string.isRequired,
     colored: PropTypes.bool,
-    network: PropTypes.string,
-    provider: PropTypes.object,
   }
 
   static contextTypes = {
@@ -33,12 +19,11 @@ export default class NetworkDisplay extends Component {
   }
 
   renderNetworkIcon() {
-    const { network } = this.props
-    const networkClass = networkIdToTypeMap[network]
+    const { networkType } = this.props
 
-    return networkClass ? (
+    return networkType ? (
       <div
-        className={`network-display__icon network-display__icon--${networkClass}`}
+        className={`network-display__icon network-display__icon--${networkType}`}
       />
     ) : (
       <div
@@ -52,24 +37,19 @@ export default class NetworkDisplay extends Component {
   }
 
   render() {
-    const {
-      colored,
-      network,
-      provider: { type, nickname },
-    } = this.props
-    const networkClass = networkIdToTypeMap[network]
+    const { colored, networkNickname, networkType } = this.props
 
     return (
       <div
         className={classnames('network-display__container', {
           'network-display__container--colored': colored,
-          [`network-display__container--${networkClass}`]:
-            colored && networkClass,
+          [`network-display__container--${networkType}`]:
+            colored && networkType,
         })}
       >
-        {networkClass ? (
+        {networkType ? (
           <div
-            className={`network-display__icon network-display__icon--${networkClass}`}
+            className={`network-display__icon network-display__icon--${networkType}`}
           />
         ) : (
           <div
@@ -81,7 +61,9 @@ export default class NetworkDisplay extends Component {
           />
         )}
         <div className="network-display__name">
-          {type === 'rpc' && nickname ? nickname : this.context.t(type)}
+          {networkType === NETWORK_TYPE_RPC && networkNickname
+            ? networkNickname
+            : this.context.t(networkType)}
         </div>
       </div>
     )
diff --git a/ui/app/components/app/network-display/network-display.container.js b/ui/app/components/app/network-display/network-display.container.js
index 99a14fff4..136336448 100644
--- a/ui/app/components/app/network-display/network-display.container.js
+++ b/ui/app/components/app/network-display/network-display.container.js
@@ -1,10 +1,14 @@
 import { connect } from 'react-redux'
 import NetworkDisplay from './network-display.component'
 
-const mapStateToProps = ({ metamask: { network, provider } }) => {
+const mapStateToProps = ({
+  metamask: {
+    provider: { nickname, type },
+  },
+}) => {
   return {
-    network,
-    provider,
+    networkNickname: nickname,
+    networkType: type,
   }
 }
 
diff --git a/ui/app/components/app/signature-request-original/signature-request-original.component.js b/ui/app/components/app/signature-request-original/signature-request-original.component.js
index b961f4def..f20933ad9 100644
--- a/ui/app/components/app/signature-request-original/signature-request-original.component.js
+++ b/ui/app/components/app/signature-request-original/signature-request-original.component.js
@@ -7,7 +7,7 @@ import { ObjectInspector } from 'react-inspector'
 import {
   ENVIRONMENT_TYPE_NOTIFICATION,
   MESSAGE_TYPE,
-} from '../../../../../app/scripts/lib/enums'
+} from '../../../../../shared/constants/app'
 import { getEnvironmentType } from '../../../../../app/scripts/lib/util'
 import Identicon from '../../ui/identicon'
 import AccountListItem from '../account-list-item'
diff --git a/ui/app/components/app/signature-request-original/signature-request-original.container.js b/ui/app/components/app/signature-request-original/signature-request-original.container.js
index 9a421aa67..7c1749fd5 100644
--- a/ui/app/components/app/signature-request-original/signature-request-original.container.js
+++ b/ui/app/components/app/signature-request-original/signature-request-original.container.js
@@ -2,7 +2,7 @@ import { connect } from 'react-redux'
 import { compose } from 'redux'
 import { withRouter } from 'react-router-dom'
 
-import { MESSAGE_TYPE } from '../../../../../app/scripts/lib/enums'
+import { MESSAGE_TYPE } from '../../../../../shared/constants/app'
 import { goHome } from '../../../store/actions'
 import {
   accountsWithSendEtherInfoSelector,
diff --git a/ui/app/components/app/signature-request/signature-request.constants.js b/ui/app/components/app/signature-request/signature-request.constants.js
index 9cf241928..7311a7a18 100644
--- a/ui/app/components/app/signature-request/signature-request.constants.js
+++ b/ui/app/components/app/signature-request/signature-request.constants.js
@@ -1,3 +1,3 @@
-import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../../shared/constants/app'
 
 export { ENVIRONMENT_TYPE_NOTIFICATION }
diff --git a/ui/app/components/app/signature-request/signature-request.container.js b/ui/app/components/app/signature-request/signature-request.container.js
index 0a521db4b..0c69f1c7a 100644
--- a/ui/app/components/app/signature-request/signature-request.container.js
+++ b/ui/app/components/app/signature-request/signature-request.container.js
@@ -2,7 +2,7 @@ import { connect } from 'react-redux'
 import { clearConfirmTransaction } from '../../../ducks/confirm-transaction/confirm-transaction.duck'
 import { accountsWithSendEtherInfoSelector } from '../../../selectors'
 import { getAccountByAddress } from '../../../helpers/utils/util'
-import { MESSAGE_TYPE } from '../../../../../app/scripts/lib/enums'
+import { MESSAGE_TYPE } from '../../../../../shared/constants/app'
 import SignatureRequest from './signature-request.component'
 
 function mapStateToProps(state) {
diff --git a/ui/app/components/app/wallet-overview/eth-overview.js b/ui/app/components/app/wallet-overview/eth-overview.js
index 4a550fcef..69aef6382 100644
--- a/ui/app/components/app/wallet-overview/eth-overview.js
+++ b/ui/app/components/app/wallet-overview/eth-overview.js
@@ -34,7 +34,7 @@ import {
   setSwapsFromToken,
 } from '../../../ducks/swaps/swaps'
 import IconButton from '../../ui/icon-button'
-import { MAINNET_CHAIN_ID } from '../../../../../app/scripts/controllers/network/enums'
+import { MAINNET_CHAIN_ID } from '../../../../../shared/constants/network'
 import WalletOverview from './wallet-overview'
 
 const EthOverview = ({ className }) => {
diff --git a/ui/app/components/app/wallet-overview/token-overview.js b/ui/app/components/app/wallet-overview/token-overview.js
index 3a2cfab90..58b5673db 100644
--- a/ui/app/components/app/wallet-overview/token-overview.js
+++ b/ui/app/components/app/wallet-overview/token-overview.js
@@ -27,7 +27,7 @@ import {
   getCurrentKeyring,
   getCurrentChainId,
 } from '../../../selectors/selectors'
-import { MAINNET_CHAIN_ID } from '../../../../../app/scripts/controllers/network/enums'
+import { MAINNET_CHAIN_ID } from '../../../../../shared/constants/network'
 
 import SwapIcon from '../../ui/icon/swap-icon.component'
 import SendIcon from '../../ui/icon/overview-send-icon.component'
diff --git a/ui/app/components/ui/typography/index.js b/ui/app/components/ui/typography/index.js
new file mode 100644
index 000000000..648ce1725
--- /dev/null
+++ b/ui/app/components/ui/typography/index.js
@@ -0,0 +1 @@
+export { default } from './typography'
diff --git a/ui/app/components/ui/typography/typography.js b/ui/app/components/ui/typography/typography.js
new file mode 100644
index 000000000..93990b00b
--- /dev/null
+++ b/ui/app/components/ui/typography/typography.js
@@ -0,0 +1,58 @@
+import React from 'react'
+import classnames from 'classnames'
+import PropTypes from 'prop-types'
+import { COLORS, TYPOGRAPHY } from '../../../helpers/constants/design-system'
+
+const { H6, H7, H8, H9 } = TYPOGRAPHY
+
+export default function Typography({
+  variant = TYPOGRAPHY.Paragraph,
+  className,
+  color = COLORS.BLACK,
+  tag,
+  children,
+  spacing = 1,
+  fontWeight = 'normal',
+  align,
+}) {
+  const computedClassName = classnames(
+    'typography',
+    className,
+    `typography--${variant}`,
+    `typography--align-${align}`,
+    `typography--spacing-${spacing}`,
+    `typography--color-${color}`,
+    `typography--weight-${fontWeight}`,
+  )
+
+  let Tag = tag ?? variant
+
+  if (Tag === TYPOGRAPHY.Paragraph) {
+    Tag = 'p'
+  } else if ([H7, H8, H9].includes(Tag)) {
+    Tag = H6
+  }
+
+  return <Tag className={computedClassName}>{children}</Tag>
+}
+
+Typography.propTypes = {
+  variant: PropTypes.oneOf(Object.values(TYPOGRAPHY)),
+  children: PropTypes.node.isRequired,
+  color: PropTypes.oneOf(Object.values(COLORS)),
+  className: PropTypes.string,
+  align: PropTypes.oneOf(['center', 'right']),
+  spacing: PropTypes.oneOf([1, 2, 3, 4, 5, 6, 7, 8]),
+  fontWeight: PropTypes.oneOf(['bold', 'normal']),
+  tag: PropTypes.oneOf([
+    'p',
+    'h1',
+    'h2',
+    'h3',
+    'h4',
+    'h5',
+    'h6',
+    'span',
+    'div',
+  ]),
+}
diff --git a/ui/app/components/ui/typography/typography.scss b/ui/app/components/ui/typography/typography.scss
new file mode 100644
index 000000000..e377f31d2
--- /dev/null
+++ b/ui/app/components/ui/typography/typography.scss
@@ -0,0 +1,38 @@
+@use "design-system";
+@use "sass:map";
+
+.typography {
+  @include design-system.Paragraph;
+
+  @each $variant in map.keys(design-system.$typography-variants) {
+    &--#{$variant} {
+      @include design-system.typography($variant);
+    }
+  }
+
+  @each $variant, $color in design-system.$color-map {
+    &--color-#{$variant} {
+      color: $color;
+    }
+  }
+
+  @each $variant, $weight in design-system.$typography-font-weights {
+    &--weight-#{$variant} {
+      font-weight: $weight;
+    }
+  }
+
+  &--align-center {
+    text-align: center;
+  }
+
+  &--align-right {
+    text-align: right;
+  }
+
+  @for $i from 1 through 8 {
+    &--spacing-#{$i} {
+      margin: #{$i * 4}px auto;
+    }
+  }
+}
diff --git a/ui/app/components/ui/typography/typography.stories.js b/ui/app/components/ui/typography/typography.stories.js
new file mode 100644
index 000000000..68d567e35
--- /dev/null
+++ b/ui/app/components/ui/typography/typography.stories.js
@@ -0,0 +1,53 @@
+import React from 'react'
+import { number, select, text } from '@storybook/addon-knobs'
+import { COLORS, TYPOGRAPHY } from '../../../helpers/constants/design-system'
+import Typography from '.'
+
+export default {
+  title: 'Typography',
+}
+
+const fontWeightOptions = {
+  bold: 'bold',
+  normal: 'normal',
+}
+
+const alignOptions = {
+  left: undefined,
+  center: 'center',
+  right: 'right',
+}
+
+export const list = () => (
+  <div style={{ width: '80%', flexDirection: 'column' }}>
+    {Object.values(TYPOGRAPHY).map((variant) => (
+      <div key={variant} style={{ width: '100%' }}>
+        <Typography
+          variant={variant}
+          color={select('color', COLORS, COLORS.BLACK)}
+          spacing={number('spacing', 1, { range: true, min: 1, max: 8 })}
+          align={select('align', alignOptions, undefined)}
+          fontWeight={select('font weight', fontWeightOptions, 'normal')}
+        >
+          {variant}
+        </Typography>
+      </div>
+    ))}
+  </div>
+)
+
+export const TheQuickOrangeFox = () => (
+  <div style={{ width: '80%', flexDirection: 'column' }}>
+    <div style={{ width: '100%' }}>
+      <Typography
+        color={select('color', COLORS, COLORS.BLACK)}
+        variant={select('variant', TYPOGRAPHY, TYPOGRAPHY.Paragraph)}
+        spacing={number('spacing', 1, { range: true, min: 1, max: 8 })}
+        align={select('align', alignOptions, undefined)}
+        fontWeight={select('font weight', fontWeightOptions, 'normal')}
+      >
+        {text('content', 'The quick orange fox jumped over the lazy dog.')}
+      </Typography>
+    </div>
+  </div>
+)
diff --git a/ui/app/components/ui/ui-components.scss b/ui/app/components/ui/ui-components.scss
index 2c7c1163b..3d5e5446c 100644
--- a/ui/app/components/ui/ui-components.scss
+++ b/ui/app/components/ui/ui-components.scss
@@ -37,5 +37,6 @@
 @import 'toggle-button/index';
 @import 'token-balance/index';
 @import 'tooltip/index';
+@import 'typography/typography';
 @import 'unit-input/index';
 @import 'url-icon/index';
diff --git a/ui/app/css/design-system/colors.scss b/ui/app/css/design-system/colors.scss
index c945c0de1..a1383b661 100644
--- a/ui/app/css/design-system/colors.scss
+++ b/ui/app/css/design-system/colors.scss
@@ -74,3 +74,66 @@ $accent-pink: #ff45d8;
 $neutral-white: #fff;
 $neutral-black: $Black-100;
 $neutral-grey: $Grey-500;
+
+// Everything below this line is part of the new color system
+$primary-1: #037dd6;
+$primary-2: #eaf6ff;
+$primary-3: #0260a4;
+
+$secondary-1: #f66a0a;
+$secondary-2: #fef5ef;
+$secondary-3: #c65507;
+
+$error-1: #d73a49;
+$error-2: #fcf2f3;
+$error-3: #b92534;
+
+$alert-1: #ffd33d;
+$alert-2: #fefcde;
+$alert-3: #f8c000;
+
+$success-1: #4cd964;
+$success-2: #caf4d1;
+$success-3: #219e37;
+
+$ui-black: #24292e;
+$ui-white: #fff;
+$ui-1: #f2f3f4;
+$ui-2: #d6d9dc;
+$ui-3: #bbc0c5;
+$ui-4: #6a737d;
+
+$mainnet: #29b6af;
+$ropsten: #ff4a8d;
+$kovan: #9064ff;
+$rinkeby: #f6c343;
+$goerli: #3099f2;
+
+$color-map: (
+  'ui-1': $ui-1,
+  'ui-2': $ui-2,
+  'ui-3': $ui-3,
+  'ui-4': $ui-4,
+  'white': $ui-white,
+  'black': $ui-black,
+  'primary-1': $primary-1,
+  'primary-2': $primary-2,
+  'primary-3': $primary-3,
+  'secondary-1': $secondary-1,
+  'secondary-2': $secondary-2,
+  'secondary-3': $secondary-3,
+  'alert-1': $alert-1,
+  'alert-2': $alert-2,
+  'alert-3': $alert-3,
+  'error-1': $error-1,
+  'error-2': $error-2,
+  'error-3': $error-3,
+  'success-1': $success-1,
+  'success-2': $success-2,
+  'success-3': $success-3,
+  'mainnet': $mainnet,
+  'ropsten': $ropsten,
+  'kovan': $kovan,
+  'rinkeby': $rinkeby,
+  'goerli': $goerli,
+);
diff --git a/ui/app/css/design-system/index.scss b/ui/app/css/design-system/index.scss
index 2d85fcae3..d4f8980b9 100644
--- a/ui/app/css/design-system/index.scss
+++ b/ui/app/css/design-system/index.scss
@@ -1,5 +1,5 @@
-@import 'breakpoints';
-@import 'colors';
-@import 'deprecated-colors';
-@import 'typography';
-@import 'z-index';
+@forward 'breakpoints';
+@forward 'colors';
+@forward 'deprecated-colors';
+@forward 'typography';
+@forward 'z-index';
diff --git a/ui/app/css/design-system/typography.scss b/ui/app/css/design-system/typography.scss
index 1d6e1a522..ff0725ea8 100644
--- a/ui/app/css/design-system/typography.scss
+++ b/ui/app/css/design-system/typography.scss
@@ -69,89 +69,80 @@ $fa-font-path: 'fonts/fontawesome';
 
 $font-family: Euclid, Roboto, Helvetica, Arial, sans-serif;
 
-$font-size-h1: 2.5rem;
-$font-size-h2: 2rem;
-$font-size-h3: 1.5rem;
-$font-size-h4: 1.125rem;
-$font-size-h5: 1rem;
-$font-size-h6: 0.875rem;
-$font-size-paragraph: 1rem;
-$font-size-h7: 0.75rem;
-$font-size-h8: 0.625rem;
-$font-size-h9: 0.5rem;
-
-// Typography
-@mixin H1 {
-  font-style: normal;
-  font-weight: normal;
-  font-size: $font-size-h1;
+$typography-variants: (
+  'h1': 2.5rem,
+  'h2': 2rem,
+  'h3': 1.5rem,
+  'h4': 1.125rem,
+  'h5': 1rem,
+  'h6': 0.875rem,
+  'paragraph': 1rem,
+  'h7': 0.75rem,
+  'h8': 0.625rem,
+  'h9': 0.5rem,
+);
+
+$typography-font-weights: (
+  'bold': 700,
+  'normal': 400,
+);
+
+$font-size-h1: map-get($typography-variants, 'h1');
+$font-size-h2: map-get($typography-variants, 'h2');
+$font-size-h3: map-get($typography-variants, 'h3');
+$font-size-h4: map-get($typography-variants, 'h4');
+$font-size-h5: map-get($typography-variants, 'h5');
+$font-size-h6: map-get($typography-variants, 'h6');
+$font-size-paragraph: map-get($typography-variants, 'paragraph');
+$font-size-h7: map-get($typography-variants, 'h7');
+$font-size-h8: map-get($typography-variants, 'h8');
+$font-size-h9: map-get($typography-variants, 'h9');
+
+@mixin typography($variant) {
+  font-size: map-get($typography-variants, $variant);
   font-family: $font-family;
   line-height: 140%;
+  font-style: normal;
+  font-weight: normal;
 }
 
+// Typography
+@mixin H1 {
+  @include typography('h1');
+}
 
 @mixin H2 {
-  font-style: normal;
-  font-weight: normal;
-  font-size: $font-size-h2;
-  font-family: $font-family;
-  line-height: 140%;
+  @include typography('h2');
 }
 
 @mixin H3 {
-  font-style: normal;
-  font-weight: normal;
-  font-size: $font-size-h3;
-  font-family: $font-family;
-  line-height: 140%;
+  @include typography('h3');
 }
 
 @mixin H4 {
-  font-style: normal;
-  font-weight: normal;
-  font-size: $font-size-h4;
-  font-family: $font-family;
-  line-height: 140%;
+  @include typography('h4');
 }
 
 @mixin H5 {
-  font-style: normal;
-  font-weight: normal;
-  font-size: $font-size-h5;
-  line-height: 140%;
+  @include typography('h5');
 }
 
 @mixin H6 {
-  font-style: normal;
-  font-weight: normal;
-  font-size: $font-size-h6; // 14px @default
-  line-height: 140%;
+  @include typography('h6');
 }
 
 @mixin Paragraph {
-  font-style: normal;
-  font-weight: normal;
-  font-size: $font-size-paragraph;
-  line-height: 140%;
+  @include typography('paragraph');
 }
 
 @mixin H7 {
-  font-style: normal;
-  font-weight: normal;
-  font-size: $font-size-h7;
-  line-height: 140%;
+  @include typography('h7');
 }
 
 @mixin H8 {
-  font-style: normal;
-  font-weight: normal;
-  font-size: $font-size-h8;
-  line-height: 140%;
+  @include typography('h8');
 }
 
 @mixin H9 {
-  font-style: normal;
-  font-weight: normal;
-  font-size: $font-size-h9;
-  line-height: 140%;
+  @include typography('h9');
 }
diff --git a/ui/app/ducks/gas/gas.duck.js b/ui/app/ducks/gas/gas.duck.js
index 83b15ecf1..1bcc5d417 100644
--- a/ui/app/ducks/gas/gas.duck.js
+++ b/ui/app/ducks/gas/gas.duck.js
@@ -1,8 +1,10 @@
 import { cloneDeep } from 'lodash'
 import BigNumber from 'bignumber.js'
 import { getStorageItem, setStorageItem } from '../../../lib/storage-helpers'
-
 import { decGWEIToHexWEI } from '../../helpers/utils/conversions.util'
+import getFetchWithTimeout from '../../../../shared/modules/fetch-with-timeout'
+
+const fetchWithTimeout = getFetchWithTimeout(30000)
 
 // Actions
 const BASIC_GAS_ESTIMATE_LOADING_FINISHED =
@@ -97,7 +99,7 @@ export function basicGasEstimatesLoadingFinished() {
 
 async function basicGasPriceQuery() {
   const url = `https://api.metaswap.codefi.network/gasPrices`
-  return await window.fetch(url, {
+  return await fetchWithTimeout(url, {
     headers: {},
     referrer: 'https://api.metaswap.codefi.network/gasPrices',
     referrerPolicy: 'no-referrer-when-downgrade',
diff --git a/ui/app/ducks/metamask/metamask.js b/ui/app/ducks/metamask/metamask.js
index 24180f0d3..cdc644a02 100644
--- a/ui/app/ducks/metamask/metamask.js
+++ b/ui/app/ducks/metamask/metamask.js
@@ -1,5 +1,6 @@
 import * as actionConstants from '../../store/actionConstants'
 import { ALERT_TYPES } from '../../../../shared/constants/alerts'
+import { NETWORK_TYPE_RPC } from '../../../../shared/constants/network'
 
 export default function reduceMetamask(state = {}, action) {
   const metamaskState = {
@@ -63,7 +64,7 @@ export default function reduceMetamask(state = {}, action) {
       return {
         ...metamaskState,
         provider: {
-          type: 'rpc',
+          type: NETWORK_TYPE_RPC,
           rpcUrl: action.value,
         },
       }
diff --git a/ui/app/helpers/constants/common.js b/ui/app/helpers/constants/common.js
index 573bab820..7a0503112 100644
--- a/ui/app/helpers/constants/common.js
+++ b/ui/app/helpers/constants/common.js
@@ -5,14 +5,6 @@ export const WEI = 'WEI'
 export const PRIMARY = 'PRIMARY'
 export const SECONDARY = 'SECONDARY'
 
-export const NETWORK_TYPES = {
-  KOVAN: 'kovan',
-  MAINNET: 'mainnet',
-  RINKEBY: 'rinkeby',
-  ROPSTEN: 'ropsten',
-  GOERLI: 'goerli',
-}
-
 export const GAS_ESTIMATE_TYPES = {
   SLOW: 'SLOW',
   AVERAGE: 'AVERAGE',
diff --git a/ui/app/helpers/constants/design-system.js b/ui/app/helpers/constants/design-system.js
new file mode 100644
index 000000000..6d6512eba
--- /dev/null
+++ b/ui/app/helpers/constants/design-system.js
@@ -0,0 +1,41 @@
+export const COLORS = {
+  UI1: 'ui-1',
+  UI2: 'ui-2',
+  UI3: 'ui-3',
+  UI4: 'ui-4',
+  BLACK: 'black',
+  WHITE: 'white',
+  PRIMARY1: 'primary-1',
+  PRIMARY2: 'primary-2',
+  PRIMARY3: 'primary-3',
+  SECONDARY1: 'secondary-1',
+  SECONDARY2: 'secondary-2',
+  SECONDARY3: 'secondary-3',
+  SUCCESS1: 'success-1',
+  SUCCESS2: 'success-2',
+  SUCCESS3: 'success-3',
+  ERROR1: 'error1',
+  ERROR2: 'error2',
+  ERROR3: 'error3',
+  ALERT1: 'alert-1',
+  ALERT2: 'alert-2',
+  ALERT3: 'alert-3',
+  MAINNET: 'mainnet',
+  ROPSTEN: 'ropsten',
+  KOVAN: 'kovan',
+  RINKEBY: 'rinkeby',
+  GOERLI: 'goerli',
+}
+
+export const TYPOGRAPHY = {
+  H1: 'h1',
+  H2: 'h2',
+  H3: 'h3',
+  H4: 'h4',
+  H5: 'h5',
+  H6: 'h6',
+  H7: 'h7',
+  H8: 'h8',
+  H9: 'h9',
+  Paragraph: 'paragraph',
+}
diff --git a/ui/app/helpers/utils/fetch-with-cache.js b/ui/app/helpers/utils/fetch-with-cache.js
index ca2bbd7f0..a903680c4 100644
--- a/ui/app/helpers/utils/fetch-with-cache.js
+++ b/ui/app/helpers/utils/fetch-with-cache.js
@@ -1,5 +1,5 @@
 import { getStorageItem, setStorageItem } from '../../../lib/storage-helpers'
-import fetchWithTimeout from '../../../../app/scripts/lib/fetch-with-timeout'
+import getFetchWithTimeout from '../../../../shared/modules/fetch-with-timeout'
 
 const fetchWithCache = async (
   url,
@@ -29,8 +29,8 @@ const fetchWithCache = async (
     return cachedResponse
   }
   fetchOptions.headers.set('Content-Type', 'application/json')
-  const _fetch = timeout ? fetchWithTimeout({ timeout }) : window.fetch
-  const response = await _fetch(url, {
+  const fetchWithTimeout = getFetchWithTimeout(timeout)
+  const response = await fetchWithTimeout(url, {
     referrerPolicy: 'no-referrer-when-downgrade',
     body: null,
     method: 'GET',
diff --git a/ui/app/helpers/utils/i18n-helper.js b/ui/app/helpers/utils/i18n-helper.js
index 140a12fff..bb8932683 100644
--- a/ui/app/helpers/utils/i18n-helper.js
+++ b/ui/app/helpers/utils/i18n-helper.js
@@ -1,9 +1,12 @@
 // cross-browser connection to extension i18n API
 import React from 'react'
 import log from 'loglevel'
-
 import * as Sentry from '@sentry/browser'
 
+import getFetchWithTimeout from '../../../../shared/modules/fetch-with-timeout'
+
+const fetchWithTimeout = getFetchWithTimeout(30000)
+
 const warned = {}
 const missingMessageErrors = {}
 const missingSubstitutionErrors = {}
@@ -95,7 +98,7 @@ export const getMessage = (localeCode, localeMessages, key, substitutions) => {
 
 export async function fetchLocale(localeCode) {
   try {
-    const response = await window.fetch(
+    const response = await fetchWithTimeout(
       `./_locales/${localeCode}/messages.json`,
     )
     return await response.json()
@@ -120,7 +123,7 @@ export async function loadRelativeTimeFormatLocaleData(localeCode) {
 }
 
 async function fetchRelativeTimeFormatData(languageTag) {
-  const response = await window.fetch(
+  const response = await fetchWithTimeout(
     `./intl/${languageTag}/relative-time-format-data.json`,
   )
   return await response.json()
diff --git a/ui/app/helpers/utils/util.js b/ui/app/helpers/utils/util.js
index 020ed9325..b88abc876 100644
--- a/ui/app/helpers/utils/util.js
+++ b/ui/app/helpers/utils/util.js
@@ -4,6 +4,9 @@ import BigNumber from 'bignumber.js'
 import ethUtil from 'ethereumjs-util'
 import { DateTime } from 'luxon'
 import { addHexPrefix } from '../../../../app/scripts/lib/util'
+import getFetchWithTimeout from '../../../../shared/modules/fetch-with-timeout'
+
+const fetchWithTimeout = getFetchWithTimeout(30000)
 
 // formatData :: ( date: <Unix Timestamp> ) -> String
 export function formatDate(date, format = "M/d/y 'at' T") {
@@ -478,19 +481,17 @@ export async function jsonRpcRequest(rpcUrl, rpcMethod, rpcParams = []) {
     headers.Authorization = `Basic ${encodedAuth}`
     fetchUrl = `${origin}${pathname}${search}`
   }
-  const jsonRpcResponse = await window
-    .fetch(fetchUrl, {
-      method: 'POST',
-      body: JSON.stringify({
-        id: Date.now().toString(),
-        jsonrpc: '2.0',
-        method: rpcMethod,
-        params: rpcParams,
-      }),
-      headers,
-      cache: 'default',
-    })
-    .then((httpResponse) => httpResponse.json())
+  const jsonRpcResponse = await fetchWithTimeout(fetchUrl, {
+    method: 'POST',
+    body: JSON.stringify({
+      id: Date.now().toString(),
+      jsonrpc: '2.0',
+      method: rpcMethod,
+      params: rpcParams,
+    }),
+    headers,
+    cache: 'default',
+  }).then((httpResponse) => httpResponse.json())
 
   if (
     !jsonRpcResponse ||
diff --git a/ui/app/pages/confirm-add-suggested-token/confirm-add-suggested-token.component.js b/ui/app/pages/confirm-add-suggested-token/confirm-add-suggested-token.component.js
index 2ef4e0ea3..b65af863b 100644
--- a/ui/app/pages/confirm-add-suggested-token/confirm-add-suggested-token.component.js
+++ b/ui/app/pages/confirm-add-suggested-token/confirm-add-suggested-token.component.js
@@ -4,7 +4,7 @@ import Button from '../../components/ui/button'
 import Identicon from '../../components/ui/identicon'
 import TokenBalance from '../../components/ui/token-balance'
 import { getEnvironmentType } from '../../../../app/scripts/lib/util'
-import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../shared/constants/app'
 
 export default class ConfirmAddSuggestedToken extends Component {
   static contextTypes = {
diff --git a/ui/app/pages/confirm-decrypt-message/confirm-decrypt-message.component.js b/ui/app/pages/confirm-decrypt-message/confirm-decrypt-message.component.js
index a9f68d388..bb5366bfd 100644
--- a/ui/app/pages/confirm-decrypt-message/confirm-decrypt-message.component.js
+++ b/ui/app/pages/confirm-decrypt-message/confirm-decrypt-message.component.js
@@ -9,7 +9,7 @@ import Identicon from '../../components/ui/identicon'
 import Tooltip from '../../components/ui/tooltip'
 import Copy from '../../components/ui/icon/copy-icon.component'
 
-import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../shared/constants/app'
 import { getEnvironmentType } from '../../../../app/scripts/lib/util'
 import { conversionUtil } from '../../helpers/utils/conversion-util'
 
diff --git a/ui/app/pages/confirm-encryption-public-key/confirm-encryption-public-key.component.js b/ui/app/pages/confirm-encryption-public-key/confirm-encryption-public-key.component.js
index c3d1dfaa2..a1c1178f7 100644
--- a/ui/app/pages/confirm-encryption-public-key/confirm-encryption-public-key.component.js
+++ b/ui/app/pages/confirm-encryption-public-key/confirm-encryption-public-key.component.js
@@ -5,7 +5,7 @@ import AccountListItem from '../../components/app/account-list-item'
 import Button from '../../components/ui/button'
 import Identicon from '../../components/ui/identicon'
 
-import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../shared/constants/app'
 import { getEnvironmentType } from '../../../../app/scripts/lib/util'
 import { conversionUtil } from '../../helpers/utils/conversion-util'
 
diff --git a/ui/app/pages/confirm-transaction-base/confirm-transaction-base.component.js b/ui/app/pages/confirm-transaction-base/confirm-transaction-base.component.js
index 24f452182..0b7d82ae0 100644
--- a/ui/app/pages/confirm-transaction-base/confirm-transaction-base.component.js
+++ b/ui/app/pages/confirm-transaction-base/confirm-transaction-base.component.js
@@ -1,7 +1,7 @@
 import ethUtil from 'ethereumjs-util'
 import React, { Component } from 'react'
 import PropTypes from 'prop-types'
-import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../shared/constants/app'
 import { getEnvironmentType } from '../../../../app/scripts/lib/util'
 import ConfirmPageContainer, {
   ConfirmDetailRow,
diff --git a/ui/app/pages/confirm-transaction-switch/confirm-transaction-switch.component.js b/ui/app/pages/confirm-transaction-switch/confirm-transaction-switch.component.js
index 88dd10084..0de4f2951 100644
--- a/ui/app/pages/confirm-transaction-switch/confirm-transaction-switch.component.js
+++ b/ui/app/pages/confirm-transaction-switch/confirm-transaction-switch.component.js
@@ -14,7 +14,7 @@ import {
   DECRYPT_MESSAGE_REQUEST_PATH,
   ENCRYPTION_PUBLIC_KEY_REQUEST_PATH,
 } from '../../helpers/constants/routes'
-import { MESSAGE_TYPE } from '../../../../app/scripts/lib/enums'
+import { MESSAGE_TYPE } from '../../../../shared/constants/app'
 import { TRANSACTION_CATEGORIES } from '../../../../shared/constants/transaction'
 
 export default class ConfirmTransactionSwitch extends Component {
diff --git a/ui/app/pages/confirm-transaction/conf-tx.js b/ui/app/pages/confirm-transaction/conf-tx.js
index cbf700548..3298baae6 100644
--- a/ui/app/pages/confirm-transaction/conf-tx.js
+++ b/ui/app/pages/confirm-transaction/conf-tx.js
@@ -10,7 +10,7 @@ import SignatureRequest from '../../components/app/signature-request'
 import SignatureRequestOriginal from '../../components/app/signature-request-original'
 import Loading from '../../components/ui/loading-screen'
 import { getMostRecentOverviewPage } from '../../ducks/history/history'
-import { MESSAGE_TYPE } from '../../../../app/scripts/lib/enums'
+import { MESSAGE_TYPE } from '../../../../shared/constants/app'
 import { TRANSACTION_STATUSES } from '../../../../shared/constants/transaction'
 
 function mapStateToProps(state) {
diff --git a/ui/app/pages/create-account/connect-hardware/account-list.js b/ui/app/pages/create-account/connect-hardware/account-list.js
index b819c81be..2cf315ae7 100644
--- a/ui/app/pages/create-account/connect-hardware/account-list.js
+++ b/ui/app/pages/create-account/connect-hardware/account-list.js
@@ -90,7 +90,7 @@ class AccountList extends Component {
                 name="selectedAccount"
                 id={`address-${idx}`}
                 value={account.index}
-                onChange={(e) => this.props.onAccountChange(e.target.value)}
+                onClick={(e) => this.props.onAccountChange(e.target.value)}
                 checked={
                   this.props.selectedAccount === account.index.toString()
                 }
diff --git a/ui/app/pages/error/error.component.js b/ui/app/pages/error/error.component.js
index d3fe6f756..e7e9ff6ed 100644
--- a/ui/app/pages/error/error.component.js
+++ b/ui/app/pages/error/error.component.js
@@ -1,7 +1,7 @@
 import React, { PureComponent } from 'react'
 import PropTypes from 'prop-types'
 import { getEnvironmentType } from '../../../../app/scripts/lib/util'
-import { ENVIRONMENT_TYPE_POPUP } from '../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_POPUP } from '../../../../shared/constants/app'
 
 class ErrorPage extends PureComponent {
   static contextTypes = {
diff --git a/ui/app/pages/home/home.container.js b/ui/app/pages/home/home.container.js
index fedebf4ad..ba4b9e6d4 100644
--- a/ui/app/pages/home/home.container.js
+++ b/ui/app/pages/home/home.container.js
@@ -33,7 +33,7 @@ import { getEnvironmentType } from '../../../../app/scripts/lib/util'
 import {
   ENVIRONMENT_TYPE_NOTIFICATION,
   ENVIRONMENT_TYPE_POPUP,
-} from '../../../../app/scripts/lib/enums'
+} from '../../../../shared/constants/app'
 import {
   ALERT_TYPES,
   WEB3_SHIM_USAGE_ALERT_STATES,
diff --git a/ui/app/pages/permissions-connect/permissions-connect.component.js b/ui/app/pages/permissions-connect/permissions-connect.component.js
index bb16d1425..06a4f136c 100644
--- a/ui/app/pages/permissions-connect/permissions-connect.component.js
+++ b/ui/app/pages/permissions-connect/permissions-connect.component.js
@@ -2,7 +2,7 @@ import PropTypes from 'prop-types'
 import React, { Component } from 'react'
 import { Switch, Route } from 'react-router-dom'
 import { getEnvironmentType } from '../../../../app/scripts/lib/util'
-import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../../shared/constants/app'
 import { DEFAULT_ROUTE } from '../../helpers/constants/routes'
 import PermissionPageContainer from '../../components/app/permission-page-container'
 import ChooseAccount from './choose-account'
diff --git a/ui/app/pages/routes/routes.component.js b/ui/app/pages/routes/routes.component.js
index 04db4f0e9..5aaf80124 100644
--- a/ui/app/pages/routes/routes.component.js
+++ b/ui/app/pages/routes/routes.component.js
@@ -58,7 +58,7 @@ import {
 import {
   ENVIRONMENT_TYPE_NOTIFICATION,
   ENVIRONMENT_TYPE_POPUP,
-} from '../../../../app/scripts/lib/enums'
+} from '../../../../shared/constants/app'
 import { getEnvironmentType } from '../../../../app/scripts/lib/util'
 import { TRANSACTION_STATUSES } from '../../../../shared/constants/transaction'
 
diff --git a/ui/app/pages/send/send-content/add-recipient/ens-input.component.js b/ui/app/pages/send/send-content/add-recipient/ens-input.component.js
index e8c498060..a1d884e79 100644
--- a/ui/app/pages/send/send-content/add-recipient/ens-input.component.js
+++ b/ui/app/pages/send/send-content/add-recipient/ens-input.component.js
@@ -13,7 +13,7 @@ import {
   isValidAddress,
   isValidAddressHead,
 } from '../../../../helpers/utils/util'
-import { MAINNET_NETWORK_ID } from '../../../../../../app/scripts/controllers/network/enums'
+import { MAINNET_NETWORK_ID } from '../../../../../../shared/constants/network'
 
 // Local Constants
 const ZERO_ADDRESS = '0x0000000000000000000000000000000000000000'
diff --git a/ui/app/pages/settings/contact-list-tab/contact-list-tab.container.js b/ui/app/pages/settings/contact-list-tab/contact-list-tab.container.js
index 5d9139014..101daf7ab 100644
--- a/ui/app/pages/settings/contact-list-tab/contact-list-tab.container.js
+++ b/ui/app/pages/settings/contact-list-tab/contact-list-tab.container.js
@@ -2,7 +2,7 @@ import { compose } from 'redux'
 import { connect } from 'react-redux'
 import { withRouter } from 'react-router-dom'
 import { getAddressBook } from '../../../selectors'
-import { ENVIRONMENT_TYPE_POPUP } from '../../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_POPUP } from '../../../../../shared/constants/app'
 import { getEnvironmentType } from '../../../../../app/scripts/lib/util'
 
 import {
diff --git a/ui/app/pages/settings/info-tab/index.scss b/ui/app/pages/settings/info-tab/index.scss
index 88216c64a..41187cc37 100644
--- a/ui/app/pages/settings/info-tab/index.scss
+++ b/ui/app/pages/settings/info-tab/index.scss
@@ -6,7 +6,10 @@
 
   &__logo {
     max-height: 100%;
-    max-width: 100%;
+    max-width: 50%;
+    display: block;
+    margin-left: auto;
+    margin-right: auto;
   }
 
   &__item {
diff --git a/ui/app/pages/settings/info-tab/info-tab.component.js b/ui/app/pages/settings/info-tab/info-tab.component.js
index 0e8118910..08e4777df 100644
--- a/ui/app/pages/settings/info-tab/info-tab.component.js
+++ b/ui/app/pages/settings/info-tab/info-tab.component.js
@@ -95,13 +95,6 @@ export default class InfoTab extends PureComponent {
       <div className="settings-page__body">
         <div className="settings-page__content-row">
           <div className="settings-page__content-item settings-page__content-item--without-height">
-            <div className="info-tab__logo-wrapper">
-              <img
-                src="images/info-logo.png"
-                className="info-tab__logo"
-                alt=""
-              />
-            </div>
             <div className="info-tab__item">
               <div className="info-tab__version-header">
                 {t('metamaskVersion')}
@@ -116,6 +109,9 @@ export default class InfoTab extends PureComponent {
           </div>
           {this.renderInfoLinks()}
         </div>
+        <div className="info-tab__logo-wrapper">
+          <img src="images/info-logo.png" className="info-tab__logo" alt="" />
+        </div>
       </div>
     )
   }
diff --git a/ui/app/pages/settings/networks-tab/networks-tab.component.js b/ui/app/pages/settings/networks-tab/networks-tab.component.js
index df2c0c029..00e66cca8 100644
--- a/ui/app/pages/settings/networks-tab/networks-tab.component.js
+++ b/ui/app/pages/settings/networks-tab/networks-tab.component.js
@@ -1,6 +1,7 @@
 import React, { PureComponent } from 'react'
 import PropTypes from 'prop-types'
 import classnames from 'classnames'
+import { NETWORK_TYPE_RPC } from '../../../../../shared/constants/network'
 import Button from '../../../components/ui/button'
 import LockIcon from '../../../components/ui/lock-icon'
 import {
@@ -90,7 +91,7 @@ export default class NetworksTab extends PureComponent {
     const listItemNetworkIsSelected = selectRpcUrl && selectRpcUrl === rpcUrl
     const listItemUrlIsProviderUrl = rpcUrl === providerUrl
     const listItemTypeIsProviderNonRpcType =
-      providerType !== 'rpc' && currentProviderType === providerType
+      providerType !== NETWORK_TYPE_RPC && currentProviderType === providerType
     const listItemNetworkIsCurrentProvider =
       !networkIsSelected &&
       !networksTabIsInAddMode &&
@@ -118,12 +119,12 @@ export default class NetworksTab extends PureComponent {
           className={classnames('networks-tab__networks-list-name', {
             'networks-tab__networks-list-name--selected': displayNetworkListItemAsSelected,
             'networks-tab__networks-list-name--disabled':
-              currentProviderType !== 'rpc' &&
+              currentProviderType !== NETWORK_TYPE_RPC &&
               !displayNetworkListItemAsSelected,
           })}
         >
           {label || this.context.t(labelKey)}
-          {currentProviderType !== 'rpc' && (
+          {currentProviderType !== NETWORK_TYPE_RPC && (
             <LockIcon width="14px" height="17px" fill="#cdcdcd" />
           )}
         </div>
diff --git a/ui/app/pages/settings/networks-tab/networks-tab.constants.js b/ui/app/pages/settings/networks-tab/networks-tab.constants.js
index 0271abcfc..9a9eb9699 100644
--- a/ui/app/pages/settings/networks-tab/networks-tab.constants.js
+++ b/ui/app/pages/settings/networks-tab/networks-tab.constants.js
@@ -9,7 +9,7 @@ import {
   RINKEBY_CHAIN_ID,
   ROPSTEN,
   ROPSTEN_CHAIN_ID,
-} from '../../../../../app/scripts/controllers/network/enums'
+} from '../../../../../shared/constants/network'
 
 const defaultNetworksData = [
   {
diff --git a/ui/app/pages/settings/networks-tab/networks-tab.container.js b/ui/app/pages/settings/networks-tab/networks-tab.container.js
index 94fcddc81..14f5d3929 100644
--- a/ui/app/pages/settings/networks-tab/networks-tab.container.js
+++ b/ui/app/pages/settings/networks-tab/networks-tab.container.js
@@ -10,7 +10,8 @@ import {
   showModal,
 } from '../../../store/actions'
 import { NETWORKS_FORM_ROUTE } from '../../../helpers/constants/routes'
-import { ENVIRONMENT_TYPE_FULLSCREEN } from '../../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_FULLSCREEN } from '../../../../../shared/constants/app'
+import { NETWORK_TYPE_RPC } from '../../../../../shared/constants/network'
 import { getEnvironmentType } from '../../../../../app/scripts/lib/util'
 import NetworksTab from './networks-tab.component'
 import { defaultNetworksData } from './networks-tab.constants'
@@ -37,7 +38,7 @@ const mapStateToProps = (state, ownProps) => {
     return {
       label: rpc.nickname,
       iconColor: '#6A737D',
-      providerType: 'rpc',
+      providerType: NETWORK_TYPE_RPC,
       rpcUrl: rpc.rpcUrl,
       chainId: rpc.chainId,
       ticker: rpc.ticker,
@@ -61,7 +62,7 @@ const mapStateToProps = (state, ownProps) => {
       networksToRender.find((network) => {
         return (
           network.rpcUrl === provider.rpcUrl ||
-          (network.providerType !== 'rpc' &&
+          (network.providerType !== NETWORK_TYPE_RPC &&
             network.providerType === provider.type)
         )
       }) || {}
diff --git a/ui/app/pages/settings/settings.container.js b/ui/app/pages/settings/settings.container.js
index ffade71da..d35fbbe6d 100644
--- a/ui/app/pages/settings/settings.container.js
+++ b/ui/app/pages/settings/settings.container.js
@@ -3,7 +3,7 @@ import { connect } from 'react-redux'
 import { withRouter } from 'react-router-dom'
 import { getAddressBookEntryName } from '../../selectors'
 import { isValidAddress } from '../../helpers/utils/util'
-import { ENVIRONMENT_TYPE_POPUP } from '../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_POPUP } from '../../../../shared/constants/app'
 import { getEnvironmentType } from '../../../../app/scripts/lib/util'
 import { getMostRecentOverviewPage } from '../../ducks/history/history'
 
diff --git a/ui/app/pages/swaps/index.js b/ui/app/pages/swaps/index.js
index 01c1f8f78..ca720910d 100644
--- a/ui/app/pages/swaps/index.js
+++ b/ui/app/pages/swaps/index.js
@@ -48,7 +48,7 @@ import {
   SWAP_FAILED_ERROR,
   OFFLINE_FOR_MAINTENANCE,
 } from '../../helpers/constants/swaps'
-import { MAINNET_CHAIN_ID } from '../../../../app/scripts/controllers/network/enums'
+import { MAINNET_CHAIN_ID } from '../../../../shared/constants/network'
 
 import {
   resetBackgroundSwapsState,
diff --git a/ui/app/pages/swaps/swaps.util.js b/ui/app/pages/swaps/swaps.util.js
index 81876d947..0fcc5d8a2 100644
--- a/ui/app/pages/swaps/swaps.util.js
+++ b/ui/app/pages/swaps/swaps.util.js
@@ -467,11 +467,11 @@ export function quotesToRenderableData(
     } = quote
     const sourceValue = calcTokenAmount(
       sourceAmount,
-      sourceTokenInfo.decimals || 18,
+      sourceTokenInfo.decimals,
     ).toString(10)
     const destinationValue = calcTokenAmount(
       destinationAmount,
-      destinationTokenInfo.decimals || 18,
+      destinationTokenInfo.decimals,
     ).toPrecision(8)
 
     const {
@@ -501,14 +501,11 @@ export function quotesToRenderableData(
       destinationTokenInfo.symbol === 'ETH'
         ? calcTokenAmount(
             destinationAmount,
-            destinationTokenInfo.decimals || 18,
+            destinationTokenInfo.decimals,
           ).minus(rawEthFee, 10)
         : new BigNumber(tokenConversionRate || 0, 10)
             .times(
-              calcTokenAmount(
-                destinationAmount,
-                destinationTokenInfo.decimals || 18,
-              ),
+              calcTokenAmount(destinationAmount, destinationTokenInfo.decimals),
               10,
             )
             .minus(rawEthFee, 10)
diff --git a/ui/app/pages/swaps/view-quote/tests/view-quote-price-difference.test.js b/ui/app/pages/swaps/view-quote/tests/view-quote-price-difference.test.js
index d32cc5759..bf37e0061 100644
--- a/ui/app/pages/swaps/view-quote/tests/view-quote-price-difference.test.js
+++ b/ui/app/pages/swaps/view-quote/tests/view-quote-price-difference.test.js
@@ -3,6 +3,7 @@ import React from 'react'
 import { shallow } from 'enzyme'
 import { Provider } from 'react-redux'
 import configureMockStore from 'redux-mock-store'
+import { NETWORK_TYPE_RPC } from '../../../../../../shared/constants/network'
 import ViewQuotePriceDifference from '../view-quote-price-difference'
 
 describe('View Price Quote Difference', function () {
@@ -11,7 +12,7 @@ describe('View Price Quote Difference', function () {
   const state = {
     metamask: {
       tokens: [],
-      provider: { type: 'rpc', nickname: '', rpcUrl: '' },
+      provider: { type: NETWORK_TYPE_RPC, nickname: '', rpcUrl: '' },
       preferences: { showFiatInTestnets: true },
       currentCurrency: 'usd',
       conversionRate: 600.0,
diff --git a/ui/app/pages/swaps/view-quote/view-quote.js b/ui/app/pages/swaps/view-quote/view-quote.js
index bdceee91f..6a9ab838f 100644
--- a/ui/app/pages/swaps/view-quote/view-quote.js
+++ b/ui/app/pages/swaps/view-quote/view-quote.js
@@ -83,6 +83,7 @@ export default function ViewQuote() {
   const metaMetricsEvent = useContext(MetaMetricsContext)
 
   const [dispatchedSafeRefetch, setDispatchedSafeRefetch] = useState(false)
+  const [submitClicked, setSubmitClicked] = useState(false)
   const [selectQuotePopoverShown, setSelectQuotePopoverShown] = useState(false)
   const [warningHidden, setWarningHidden] = useState(false)
   const [originalApproveAmount, setOriginalApproveAmount] = useState(null)
@@ -570,6 +571,7 @@ export default function ViewQuote() {
       </div>
       <SwapsFooter
         onSubmit={() => {
+          setSubmitClicked(true)
           if (!balanceError) {
             dispatch(signAndSendTransactions(history, metaMetricsEvent))
           } else if (destinationToken.symbol === 'ETH') {
@@ -580,7 +582,12 @@ export default function ViewQuote() {
         }}
         submitText={t('swap')}
         onCancel={async () => await dispatch(navigateBackToBuildQuote(history))}
-        disabled={balanceError || gasPrice === null || gasPrice === undefined}
+        disabled={
+          submitClicked ||
+          balanceError ||
+          gasPrice === null ||
+          gasPrice === undefined
+        }
         className={isShowingWarning && 'view-quote__thin-swaps-footer'}
         showTopBorder
       />
diff --git a/ui/app/pages/unlock-page/unlock-page.container.js b/ui/app/pages/unlock-page/unlock-page.container.js
index 222d8b04a..9284ebeba 100644
--- a/ui/app/pages/unlock-page/unlock-page.container.js
+++ b/ui/app/pages/unlock-page/unlock-page.container.js
@@ -2,7 +2,7 @@ import { connect } from 'react-redux'
 import { withRouter } from 'react-router-dom'
 import { compose } from 'redux'
 import { getEnvironmentType } from '../../../../app/scripts/lib/util'
-import { ENVIRONMENT_TYPE_POPUP } from '../../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_POPUP } from '../../../../shared/constants/app'
 import {
   DEFAULT_ROUTE,
   RESTORE_VAULT_ROUTE,
diff --git a/ui/app/selectors/permissions.js b/ui/app/selectors/permissions.js
index a463d09d0..e6dfa4db5 100644
--- a/ui/app/selectors/permissions.js
+++ b/ui/app/selectors/permissions.js
@@ -1,5 +1,5 @@
 import { forOwn } from 'lodash'
-import { CAVEAT_NAMES } from '../../../app/scripts/controllers/permissions/enums'
+import { CAVEAT_NAMES } from '../../../shared/constants/permissions'
 import {
   getMetaMaskAccountsOrdered,
   getOriginOfCurrentTab,
diff --git a/ui/app/selectors/selectors.js b/ui/app/selectors/selectors.js
index 5607476a8..9db335a85 100644
--- a/ui/app/selectors/selectors.js
+++ b/ui/app/selectors/selectors.js
@@ -1,7 +1,7 @@
 import { stripHexPrefix } from 'ethereumjs-util'
 import { createSelector } from 'reselect'
 import { addHexPrefix } from '../../../app/scripts/lib/util'
-import { NETWORK_TYPES } from '../helpers/constants/common'
+import { MAINNET, NETWORK_TYPE_RPC } from '../../../shared/constants/network'
 import {
   shortenAddress,
   checksumAddress,
@@ -21,7 +21,7 @@ export function getNetworkIdentifier(state) {
 
 export function getMetricsNetworkIdentifier(state) {
   const { provider } = state.metamask
-  return provider.type === 'rpc' ? provider.rpcUrl : provider.type
+  return provider.type === NETWORK_TYPE_RPC ? provider.rpcUrl : provider.type
 }
 
 export function getCurrentChainId(state) {
@@ -281,7 +281,7 @@ function getSuggestedTokenCount(state) {
 
 export function getIsMainnet(state) {
   const networkType = getNetworkIdentifier(state)
-  return networkType === NETWORK_TYPES.MAINNET
+  return networkType === MAINNET
 }
 
 export function getPreferences({ metamask }) {
diff --git a/ui/app/store/actions.js b/ui/app/store/actions.js
index 780bb81c1..0dd31dc9f 100644
--- a/ui/app/store/actions.js
+++ b/ui/app/store/actions.js
@@ -12,7 +12,7 @@ import {
 import { getMethodDataAsync } from '../helpers/utils/transactions.util'
 import { fetchSymbolAndDecimals } from '../helpers/utils/token-util'
 import switchDirection from '../helpers/utils/switch-direction'
-import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_NOTIFICATION } from '../../../shared/constants/app'
 import { hasUnconfirmedTransactions } from '../helpers/utils/confirm-tx.util'
 import { setCustomGasLimit } from '../ducks/gas/gas.duck'
 import txHelper from '../../lib/tx-helper'
diff --git a/ui/index.js b/ui/index.js
index 6c4541f17..3f0e172f8 100644
--- a/ui/index.js
+++ b/ui/index.js
@@ -6,7 +6,7 @@ import { render } from 'react-dom'
 import { getEnvironmentType } from '../app/scripts/lib/util'
 import { ALERT_TYPES } from '../shared/constants/alerts'
 import { SENTRY_STATE } from '../app/scripts/lib/setupSentry'
-import { ENVIRONMENT_TYPE_POPUP } from '../app/scripts/lib/enums'
+import { ENVIRONMENT_TYPE_POPUP } from '../shared/constants/app'
 import Root from './app/pages'
 import * as actions from './app/store/actions'
 import configureStore from './app/store/store'
diff --git a/ui/lib/etherscan-prefix-for-network.js b/ui/lib/etherscan-prefix-for-network.js
index 32183d1bc..82e92f3b1 100644
--- a/ui/lib/etherscan-prefix-for-network.js
+++ b/ui/lib/etherscan-prefix-for-network.js
@@ -1,4 +1,4 @@
-import * as networkEnums from '../../app/scripts/controllers/network/enums'
+import * as networkEnums from '../../shared/constants/network'
 
 /**
  * Gets the etherscan.io URL prefix for a given network ID.
diff --git a/ui/lib/webcam-utils.js b/ui/lib/webcam-utils.js
index a242186df..6c451fd21 100644
--- a/ui/lib/webcam-utils.js
+++ b/ui/lib/webcam-utils.js
@@ -4,7 +4,7 @@ import {
   ENVIRONMENT_TYPE_POPUP,
   PLATFORM_BRAVE,
   PLATFORM_FIREFOX,
-} from '../../app/scripts/lib/enums'
+} from '../../shared/constants/app'
 import { getEnvironmentType, getPlatform } from '../../app/scripts/lib/util'
 
 class WebcamUtils {
diff --git a/yarn.lock b/yarn.lock
index f7a2f4e6e..411f8b64c 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -6708,6 +6708,21 @@ chokidar@3.3.0:
   optionalDependencies:
     fsevents "~2.1.1"
 
+"chokidar@>=2.0.0 <4.0.0":
+  version "3.5.1"
+  resolved "https://registry.yarnpkg.com/chokidar/-/chokidar-3.5.1.tgz#ee9ce7bbebd2b79f49f304799d5468e31e14e68a"
+  integrity sha512-9+s+Od+W0VJJzawDma/gvBNQqkTiqYTWLuZoyAsivsI4AaWTCzHG06/TMjsf1cYe9Cb97UCEhjz7HvnPk2p/tw==
+  dependencies:
+    anymatch "~3.1.1"
+    braces "~3.0.2"
+    glob-parent "~5.1.0"
+    is-binary-path "~2.1.0"
+    is-glob "~4.0.1"
+    normalize-path "~3.0.0"
+    readdirp "~3.5.0"
+  optionalDependencies:
+    fsevents "~2.3.1"
+
 chokidar@^2.0.0, chokidar@^2.1.1, chokidar@^2.1.8:
   version "2.1.8"
   resolved "https://registry.yarnpkg.com/chokidar/-/chokidar-2.1.8.tgz#804b3a7b6a99358c3c5c61e71d8728f041cff917"
@@ -11633,6 +11648,11 @@ fsevents@~2.1.1, fsevents@~2.1.2:
   resolved "https://registry.yarnpkg.com/fsevents/-/fsevents-2.1.3.tgz#fb738703ae8d2f9fe900c33836ddebee8b97f23e"
   integrity sha512-Auw9a4AxqWpa9GUfj370BMPzzyncfBABW8Mab7BGWBYDj4Isgq+cDKtx0i6u9jcX9pQDnswsaaOTgTmA5pEjuQ==
 
+fsevents@~2.3.1:
+  version "2.3.1"
+  resolved "https://registry.yarnpkg.com/fsevents/-/fsevents-2.3.1.tgz#b209ab14c61012636c8863507edf7fb68cc54e9f"
+  integrity sha512-YR47Eg4hChJGAB1O3yEAOkGO+rlzutoICGqGo9EZ4lKWokzZRSyIW1QmTzqjtw8MJdj9srP869CuWw/hyzSiBw==
+
 fsm-event@^2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/fsm-event/-/fsm-event-2.1.0.tgz#d385716ed38f9c92feab2ba601e2aac6c0ba5a92"
@@ -12586,13 +12606,13 @@ gulp-rtlcss@^1.4.0:
     through2 "^2.0.5"
     vinyl-sourcemaps-apply "^0.2.1"
 
-gulp-sass@^4.0.0:
-  version "4.0.1"
-  resolved "https://registry.yarnpkg.com/gulp-sass/-/gulp-sass-4.0.1.tgz#7f43d117eb2d303524968a1b48494af1bc64d1d9"
-  integrity sha512-OMQEgWNggpog8Tc5v1MuI6eo+5iiPkVeLL76iBhDoEEScLUPfZlpvzmgTnLkpcqdrNodZxpz5qcv6mS2rulk3g==
+gulp-sass@^4.1.0:
+  version "4.1.0"
+  resolved "https://registry.yarnpkg.com/gulp-sass/-/gulp-sass-4.1.0.tgz#486d7443c32d42bf31a6b1573ebbdaa361de7427"
+  integrity sha512-xIiwp9nkBLcJDpmYHbEHdoWZv+j+WtYaKD6Zil/67F3nrAaZtWYN5mDwerdo7EvcdBenSAj7Xb2hx2DqURLGdA==
   dependencies:
     chalk "^2.3.0"
-    lodash.clonedeep "^4.3.2"
+    lodash "^4.17.11"
     node-sass "^4.8.3"
     plugin-error "^1.0.1"
     replace-ext "^1.0.0"
@@ -15644,6 +15664,11 @@ klaw@^1.0.0:
   optionalDependencies:
     graceful-fs "^4.1.9"
 
+klona@^2.0.4:
+  version "2.0.4"
+  resolved "https://registry.yarnpkg.com/klona/-/klona-2.0.4.tgz#7bb1e3affb0cb8624547ef7e8f6708ea2e39dfc0"
+  integrity sha512-ZRbnvdg/NxqzC7L9Uyqzf4psi1OM4Cuc+sJAkQPjO6XkQIJTNbfK2Rsmbw8fx1p2mkZdp2FZYo2+LwXYY/uwIA==
+
 knex@^0.15.2:
   version "0.15.2"
   resolved "https://registry.yarnpkg.com/knex/-/knex-0.15.2.tgz#6059b87489605f4cc87599a6d2a9d265709e9340"
@@ -16545,7 +16570,7 @@ loader-runner@^2.4.0:
   resolved "https://registry.yarnpkg.com/loader-runner/-/loader-runner-2.4.0.tgz#ed47066bfe534d7e84c4c7b9998c2a75607d9357"
   integrity sha512-Jsmr89RcXGIwivFY21FcRrisYZfvLMTWx5kOLc+JTxtpBOG6xML0vzbc6SEQG2FO9/4Fc3wW4LVcB5DmGflaRw==
 
-loader-utils@1.2.3, loader-utils@^1.0.1, loader-utils@^1.0.2, loader-utils@^1.1.0, loader-utils@^1.2.3:
+loader-utils@1.2.3, loader-utils@^1.0.2, loader-utils@^1.1.0, loader-utils@^1.2.3:
   version "1.2.3"
   resolved "https://registry.yarnpkg.com/loader-utils/-/loader-utils-1.2.3.tgz#1ff5dc6911c9f0a062531a4c04b609406108c2c7"
   integrity sha512-fkpz8ejdnEMG3s37wGL07iSBDg99O9D5yflE9RGNH3hRdx9SOwYfnGYdZOUIZitN8E+E2vkq3MUMYMvPYl5ZZA==
@@ -16646,7 +16671,7 @@ lodash.assign@^4.2.0:
   resolved "https://registry.yarnpkg.com/lodash.assign/-/lodash.assign-4.2.0.tgz#0d99f3ccd7a6d261d19bdaeb9245005d285808e7"
   integrity sha1-DZnzzNem0mHRm9rrkkUAXShYCOc=
 
-lodash.clonedeep@4.5.0, lodash.clonedeep@^4.3.2:
+lodash.clonedeep@4.5.0:
   version "4.5.0"
   resolved "https://registry.yarnpkg.com/lodash.clonedeep/-/lodash.clonedeep-4.5.0.tgz#e23f3f9c4f8fbdde872529c1071857a086e5ccef"
   integrity sha1-4j8/nE+Pvd6HJSnBBxhXoIblzO8=
@@ -16746,11 +16771,6 @@ lodash.sortby@^4.7.0:
   resolved "https://registry.yarnpkg.com/lodash.sortby/-/lodash.sortby-4.7.0.tgz#edd14c824e2cc9c1e0b0a1b42bb5210516a42438"
   integrity sha1-7dFMgk4sycHgsKG0K7UhBRakJDg=
 
-lodash.tail@^4.1.1:
-  version "4.1.1"
-  resolved "https://registry.yarnpkg.com/lodash.tail/-/lodash.tail-4.1.1.tgz#d2333a36d9e7717c8ad2f7cacafec7c32b444664"
-  integrity sha1-0jM6NtnncXyK0vfKyv7HwytERmQ=
-
 lodash.throttle@^4.1.1:
   version "4.1.1"
   resolved "https://registry.yarnpkg.com/lodash.throttle/-/lodash.throttle-4.1.1.tgz#c23e91b710242ac70c37f1e1cda9274cc39bf2f4"
@@ -18025,6 +18045,11 @@ neo-async@^2.5.0, neo-async@^2.6.1:
   resolved "https://registry.yarnpkg.com/neo-async/-/neo-async-2.6.1.tgz#ac27ada66167fa8849a6addd837f6b189ad2081c"
   integrity sha512-iyam8fBuCUpWeKPGpaNMetEocMt364qkCsfL9JuhjXX6dRnguRVOfk2GZaDpPjcOKiiXCPINZC1GczQ7iTq3Zw==
 
+neo-async@^2.6.2:
+  version "2.6.2"
+  resolved "https://registry.yarnpkg.com/neo-async/-/neo-async-2.6.2.tgz#b4aafb93e3aeb2d8174ca53cf163ab7d7308305f"
+  integrity sha512-Yd3UES5mWCSqR+qNT93S3UoYUkqAZ9lLg8a7g9rimsWmYGK8cVToA4/sF3RrshdyV3sAGMXVUmpMYOw+dLpOuw==
+
 nested-error-stacks@^2.0.0, nested-error-stacks@^2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/nested-error-stacks/-/nested-error-stacks-2.1.0.tgz#0fbdcf3e13fe4994781280524f8b96b0cdff9c61"
@@ -18255,7 +18280,7 @@ node-releases@^1.1.52, node-releases@^1.1.66:
   resolved "https://registry.yarnpkg.com/node-releases/-/node-releases-1.1.67.tgz#28ebfcccd0baa6aad8e8d4d8fe4cbc49ae239c12"
   integrity sha512-V5QF9noGFl3EymEwUYzO+3NTDpGfQB4ve6Qfnzf3UNydMhjQRVPR1DZTuvWiLzaFJYw2fmDwAfnRNEVb64hSIg==
 
-node-sass@^4.14.1, node-sass@^4.8.3:
+node-sass@^4.8.3:
   version "4.14.1"
   resolved "https://registry.yarnpkg.com/node-sass/-/node-sass-4.14.1.tgz#99c87ec2efb7047ed638fb4c9db7f3a42e2217b5"
   integrity sha512-sjCuOlvGyCJS40R8BscF5vhVlQjNN069NtQ1gSxyK1u9iqvn6tf7O1R4GNowVZfiZUCRt5MmMs1xd+4V/7Yr0g==
@@ -22428,16 +22453,23 @@ sass-graph@2.2.5:
     scss-tokenizer "^0.2.3"
     yargs "^13.3.2"
 
-sass-loader@^7.0.1:
-  version "7.0.1"
-  resolved "https://registry.yarnpkg.com/sass-loader/-/sass-loader-7.0.1.tgz#fd937259ccba3a9cfe0d5f8a98746d48adfcc261"
-  integrity sha512-MeVVJFejJELlAbA7jrRchi88PGP6U9yIfqyiG+bBC4a9s2PX+ulJB9h8bbEohtPBfZmlLhNZ0opQM9hovRXvlw==
+sass-loader@^10.1.1:
+  version "10.1.1"
+  resolved "https://registry.yarnpkg.com/sass-loader/-/sass-loader-10.1.1.tgz#4ddd5a3d7638e7949065dd6e9c7c04037f7e663d"
+  integrity sha512-W6gVDXAd5hR/WHsPicvZdjAWHBcEJ44UahgxcIE196fW2ong0ZHMPO1kZuI5q0VlvMQZh32gpv69PLWQm70qrw==
   dependencies:
-    clone-deep "^2.0.1"
-    loader-utils "^1.0.1"
-    lodash.tail "^4.1.1"
-    neo-async "^2.5.0"
-    pify "^3.0.0"
+    klona "^2.0.4"
+    loader-utils "^2.0.0"
+    neo-async "^2.6.2"
+    schema-utils "^3.0.0"
+    semver "^7.3.2"
+
+sass@^1.32.4:
+  version "1.32.4"
+  resolved "https://registry.yarnpkg.com/sass/-/sass-1.32.4.tgz#308bf29dd7f53d44ae4f06580e9a910ad9aa411e"
+  integrity sha512-N0BT0PI/t3+gD8jKa83zJJUb7ssfQnRRfqN+GIErokW6U4guBpfYl8qYB+OFLEho+QvnV5ZH1R9qhUC/Z2Ch9w==
+  dependencies:
+    chokidar ">=2.0.0 <4.0.0"
 
 sax@^1.2.1, sax@^1.2.4, sax@~1.2.4:
   version "1.2.4"