diff --git a/.travis.yml b/.travis.yml
index b187287524..a756091afb 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -29,7 +29,7 @@
 language: ruby
 
 rvm:
-  - 2.5.1
+  - 2.6.1
 
 sudo: required
 dist: trusty
diff --git a/Dockerfile b/Dockerfile
index 7647a3228a..f8a98bdf0e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:2.5-stretch
+FROM ruby:2.6-stretch
 
 ENV NODE_VERSION="10.15.0"
 ENV BUNDLER_VERSION="2.0.1"
diff --git a/Gemfile b/Gemfile
index 35880f3691..7dffdec299 100644
--- a/Gemfile
+++ b/Gemfile
@@ -28,7 +28,7 @@
 
 source 'https://rubygems.org'
 
-ruby '~> 2.5.1'
+ruby '~> 2.6.1'
 
 gem 'actionpack-xml_parser', '~> 2.0.0'
 gem 'activemodel-serializers-xml', '~> 1.0.1'
@@ -229,7 +229,7 @@ group :test do
 
   gem 'fuubar', '~> 2.3.2'
   gem 'timecop', '~> 0.9.0'
-  gem 'webmock', '~> 3.1.0', require: false
+  gem 'webmock', '~> 3.5.0', require: false
 
   gem 'equivalent-xml', '~> 0.6'
   gem 'json_spec', '~> 1.1.4'
diff --git a/Gemfile.lock b/Gemfile.lock
index 266e4ad2f3..7844aeb18d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -464,7 +464,7 @@ GEM
       rack-accept
       virtus (>= 1.0.0)
     gravatar_image_tag (1.2.0)
-    hashdiff (0.3.7)
+    hashdiff (0.3.8)
     hashery (2.1.2)
     hashie (3.6.0)
     health_check (3.0.0)
@@ -862,7 +862,7 @@ GEM
     webfinger (1.1.0)
       activesupport
       httpclient (>= 2.4)
-    webmock (3.1.0)
+    webmock (3.5.1)
       addressable (>= 2.3.6)
       crack (>= 0.3.2)
       hashdiff
@@ -1028,11 +1028,11 @@ DEPENDENCIES
   unicorn-worker-killer
   warden (~> 1.2)
   warden-basic_auth (~> 0.2.1)
-  webmock (~> 3.1.0)
+  webmock (~> 3.5.0)
   will_paginate (~> 3.1.0)
 
 RUBY VERSION
-   ruby 2.5.1p57
+   ruby 2.6.1p33
 
 BUNDLED WITH
    2.0.1
diff --git a/docs/development/development-environment-osx.md b/docs/development/development-environment-osx.md
index 7845b6a7b7..b304907bab 100644
--- a/docs/development/development-environment-osx.md
+++ b/docs/development/development-environment-osx.md
@@ -13,9 +13,9 @@ If you find any bugs or you have any recommendations for improving this tutorial
 
 We'll use [homebrew](https://brew.sh/) to install most of our requirements. Please install that first using the guide on their homepage.
 
-## Install Ruby 2.5.
+## Install Ruby 2.6.
 
-Use [rbenv](https://github.com/rbenv/rbenv) and [ruby-build](https://github.com/rbenv/ruby-build#readme) to install Ruby 2.5.0.
+Use [rbenv](https://github.com/rbenv/rbenv) and [ruby-build](https://github.com/rbenv/ruby-build#readme) to install Ruby 2.6.1.
 **Install rbenv and ruby-build**
 
 rbenv is a ruby version manager that lets you quickly switch between ruby versions.
@@ -28,23 +28,23 @@ $ brew install rbenv ruby-build
 $ rbenv init
 ```
 
-**Installing ruby-2.5**
+**Installing ruby-2.6**
 
-With both installed, we can now install the actual ruby version 2.5. You can check available ruby versions with `rbenv install --list`.
-At the time of this writing, the latest stable version is `2.5.0`, which we also require.
+With both installed, we can now install the actual ruby version 2.6. You can check available ruby versions with `rbenv install --list`.
+At the time of this writing, the latest stable version is `2.6.1`, which we also require.
 
 We suggest you install the version we require in the [Gemfile](https://github.com/opf/openproject/blob/dev/Gemfile). Search for the `ruby '~> X.Y.Z'` line
 and install that version.
 
 ```bash
 # Install the required version as read from the Gemfile
-[dev@ubuntu]# rbenv install 2.5.0
+[dev@ubuntu]# rbenv install 2.6.1
 ```
 
 This might take a while depending on whether ruby is built from source. After it is complete, you need to tell rbenv to globally activate this version
 
 ```bash
-[dev@ubuntu]# rbenv global 2.5.0
+[dev@ubuntu]# rbenv global 2.6.1
 ```
 
 You also need to install [bundler](https://github.com/bundler/bundler/), the ruby gem bundler.
@@ -108,13 +108,13 @@ You should now have an active ruby and node installation. Verify that it works w
 
 ```bash
 $ ruby --version
-ruby 2.5.0p0 (2017-12-25 revision 61468) [x86_64-darwin16]
+ruby 2.6.1p33 (2019-01-30 revision 66950) [x86_64-darwin16]
 
 $ bundler --version
-Bundler version 1.16.1
+Bundler version 2.0.1
 
 $ npm --version
-3.10.10
+6.7.0
 ```
 
 # Install OpenProject
diff --git a/docs/development/development-environment-ubuntu.md b/docs/development/development-environment-ubuntu.md
index 4a542f00a3..108c82ac21 100644
--- a/docs/development/development-environment-ubuntu.md
+++ b/docs/development/development-environment-ubuntu.md
@@ -20,9 +20,9 @@ We need an active Ruby and Node JS environment to run OpenProject. To this end,
 [dev@ubuntu]# sudo apt-get install git curl build-essential zlib1g-dev libyaml-dev libssl-dev libmysqlclient-dev libpq-dev libsqlite3-dev libreadline-dev libffi6
 ```
 
-## Install Ruby 2.5.
+## Install Ruby 2.6.
 
-Use [rbenv](https://github.com/rbenv/rbenv) and [ruby-build](https://github.com/rbenv/ruby-build#readme) to install Ruby 2.5.
+Use [rbenv](https://github.com/rbenv/rbenv) and [ruby-build](https://github.com/rbenv/ruby-build#readme) to install Ruby 2.6.
 
 
 **Install rbenv**
@@ -51,23 +51,23 @@ ruby-build is an addon to rbenv that installs ruby versions
 [dev@ubuntu]# git clone https://github.com/rbenv/ruby-build.git ~/.rbenv/plugins/ruby-build
 ```
 
-**Installing ruby-2.5**
+**Installing ruby-2.6**
 
-With both installed, we can now install the actual ruby version 2.5. You can check available ruby versions with `rbenv install --list`.
-At the time of this writing, the latest stable version is `2.5.0`, which we also require.
+With both installed, we can now install the actual ruby version 2.6. You can check available ruby versions with `rbenv install --list`.
+At the time of this writing, the latest stable version is `2.6.1`, which we also require.
 
 We suggest you install the version we require in the [Gemfile](https://github.com/opf/openproject/blob/dev/Gemfile). Search for the `ruby '~> X.Y.Z'` line
 and install that version.
 
 ```bash
 # Install the required version as read from the Gemfile
-[dev@ubuntu]# rbenv install 2.5.1
+[dev@ubuntu]# rbenv install 2.6.1
 ```
 
 This might take a while depending on whether ruby is built from source. After it is complete, you need to tell rbenv to globally activate this version
 
 ```bash
-[dev@ubuntu]# rbenv global 2.5.1
+[dev@ubuntu]# rbenv global 2.6.1
 ```
 
 You also need to install [bundler](https://github.com/bundler/bundler/), the ruby gem bundler.
@@ -144,13 +144,13 @@ You should now have an active ruby and node installation. Verify that it works w
 
 ```bash
 [dev@ubuntu]# ruby --version
-ruby 2.5.1p57 (2017-12-25 revision 61468) [x86_64-darwin16]
+ruby 2.6.1p33 (2019-01-30 revision 66950) [x86_64-darwin16]
 
 [dev@ubuntu]# bundler --version
-Bundler version 1.16.1
+Bundler version 2.0.1
 
 [dev@ubuntu]# npm --version
-6.4.1
+6.7.0
 ```
 
 # Install OpenProject
diff --git a/docs/installation/manual/README.md b/docs/installation/manual/README.md
index 2cbbe2dcee..8e2b01bb38 100644
--- a/docs/installation/manual/README.md
+++ b/docs/installation/manual/README.md
@@ -156,16 +156,16 @@ time to finish.
 [openproject@host] source ~/.profile
 [openproject@host] git clone https://github.com/sstephenson/ruby-build.git ~/.rbenv/plugins/ruby-build
 
-[openproject@host] rbenv install 2.5.3
+[openproject@host] rbenv install 2.6.1
 [openproject@host] rbenv rehash
-[openproject@host] rbenv global 2.5.3
+[openproject@host] rbenv global 2.6.1
 ```
 
 To check our Ruby installation we run `ruby --version`. It should output
 something very similar to:
 
 ```
-ruby 2.5.3pXYZ (....) [x86_64-linux]
+ruby 2.6.1pXYZ (....) [x86_64-linux]
 ```
 
 ## Installation of Node
diff --git a/docs/installation/system-requirements.md b/docs/installation/system-requirements.md
index 829af457a4..34ba08be8f 100644
--- a/docs/installation/system-requirements.md
+++ b/docs/installation/system-requirements.md
@@ -25,7 +25,7 @@ provide any official support for them.
 
 ### Dependencies
 
-* __Runtime:__ [Ruby](https://www.ruby-lang.org/en/) Version = 2.5.x
+* __Runtime:__ [Ruby](https://www.ruby-lang.org/en/) Version = 2.6.x
 * __Webserver:__ [Apache](http://httpd.apache.org/)
   or [nginx](http://nginx.org/en/docs/)
 * __Application server:__ [Phusion Passenger](https://www.phusionpassenger.com/)
diff --git a/modules/costs/spec/features/work_package_filter_spec.rb b/modules/costs/spec/features/work_package_filter_spec.rb
index ec2a7f3280..dfa4f77c2a 100644
--- a/modules/costs/spec/features/work_package_filter_spec.rb
+++ b/modules/costs/spec/features/work_package_filter_spec.rb
@@ -73,6 +73,8 @@ describe 'Filter by budget', js: true do
 
     wp_table.save_as('Some query name')
 
+    wp_table.expect_and_dismiss_notification message: 'Successful creation.'
+
     filters.remove_filter 'costObject'
 
     wp_table.expect_work_package_listed work_package_with_budget, work_package_without_budget
diff --git a/spec/support/webmock.rb b/spec/support/webmock.rb
index 95428bf05c..02543c93a8 100644
--- a/spec/support/webmock.rb
+++ b/spec/support/webmock.rb
@@ -29,10 +29,12 @@
 require 'webmock/rspec'
 
 RSpec.configure do |config|
-  # As we're using WebMock to mock and test remote HTTP requests,
-  # we require specs to selectively enable mocking of Net::HTTP et al. when the example desires.
-  # Otherwise, all requests are being mocked by default.
-  WebMock.disable!
+  config.before(:suite) do
+    # As we're using WebMock to mock and test remote HTTP requests,
+    # we require specs to selectively enable mocking of Net::HTTP et al. when the example desires.
+    # Otherwise, all requests are being mocked by default.
+    WebMock.disable!
+  end
 
   # When we enable webmock, no connections other than stubbed ones are allowed.
   # We will exempt local connections from this block, since selenium etc.