diff --git a/config/locales/de.yml b/config/locales/de.yml
index ad95e60290..6c22860746 100644
--- a/config/locales/de.yml
+++ b/config/locales/de.yml
@@ -1,77 +1,49 @@
-#-- copyright
-# OpenProject Reporting Plugin
-#
-# Copyright (C) 2010 - 2014 the OpenProject Foundation (OPF)
-#
-# This program is free software; you can redistribute it and/or
-# modify it under the terms of the GNU General Public License
-# version 3.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program; if not, write to the Free Software
-# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
-#++
-
----
 de:
-  button_save_as: "Speichern unter ..."
-
-  comments: "Kommentar"
-  cost_reports_title: "Kostenauswertungen"
-  label_cost_report: "Kostenauswertung"
-
-  description_drill_down: "Details anzeigen"
-  description_filter_selection: "Auswahl"
-  description_multi_select: "Mehrfachauswahl anzeigen"
-  description_remove_filter: "Filter entfernen"
-
-  information_restricted_depending_on_permission: "Abhängig von Ihren Berechtigungen können die Informationen auf dieser Seite eingeschränkt sein."
-
-  label_click_to_edit: "Zum Bearbeiten hier klicken."
-  label_closed: "Geschlossen"
-  label_columns: "Spalten"
-  label_cost_entry_attributes: "Attribute am Kosteneintrag"
-  label_days_ago: "in den letzten Tagen"
-  label_entry: "Kosteneintrag"
-  label_filter_text: "Filtertext"
-  label_filter_value: "Wert"
-  label_filters: "Filter"
-  label_greater: ">"
-  label_is_not_project_with_subprojects: "ist nicht (mit Unterprojekten)"
-  label_is_project_with_subprojects: "ist (mit Unterprojekten)"
-  label_work_package_attributes: "Attribute am Ticket"
-  label_less: "<"
-  label_money: "Geldwert"
-  label_month_reporting: "Monat der Buchung"
-  label_new_report: "Neue Kostenauswertung"
-  label_open: "Offen"
-  label_operator: "Operator"
-  label_private_report_plural: "Persönliche Kostenauswertungen"
-  label_progress_bar_explanation: "Kostenauswertung wird erstellt ..."
-  label_public_report_plural: "Gemeinsame Kostenauswertungen"
-  label_really_delete_question: "Diese Kostenauswertung wirklich löschen?"
-  label_rows: "Zeilen"
-  label_saving: "Speichern..."
-  label_spent_on_reporting: "Datum der Buchung"
-  label_sum: "Summe"
-  label_units: "Einheiten"
-  label_week_reporting: "Woche der Buchung"
-  label_year_reporting: "Jahr der Buchung"
-  load_query_question: "Die Kostenauswertung wird %{size} Tabellen-Zellen haben, was sehr rechenintensiv sein kann. Wollen Sie dennoch versuchen, die Kostenauswertung durch zu führen?"
-
-  permission_save_cost_reports: "Speichern gemeinsamer Kostenauswertungen"
-  permission_save_private_cost_reports: "Speichern persönlicher Kostenauswertungen"
-  project_module_reporting_module: "Kostenauswertungen"
-
-  text_costs_are_rounded_note: "Die angezeigten Werte sind gerundet. Alle Berechnungen basieren auf ungerundeten Werten."
-  toggle_multiselect: "Mehrfachauswahl aktivieren/deaktivieren"
-
-  units: "Einheiten"
-
-  validation_failure_date: "ist kein gültiges Datum"
-  validation_failure_integer: "ist keine ganze Zahl"
+  button_save_as: Speichern unter ...
+  comments: Kommentar
+  cost_reports_title: Kostenauswertungen
+  label_cost_report: Kostenauswertung
+  description_drill_down: Details anzeigen
+  description_filter_selection: Auswahl
+  description_multi_select: Mehrfachauswahl anzeigen
+  description_remove_filter: Filter entfernen
+  information_restricted_depending_on_permission: Abhängig von Ihren Berechtigungen können die Informationen auf dieser Seite eingeschränkt sein.
+  label_click_to_edit: Zum Bearbeiten hier klicken.
+  label_closed: Geschlossen
+  label_columns: Spalten
+  label_cost_entry_attributes: Attribute am Kosteneintrag
+  label_days_ago: in den letzten Tagen
+  label_entry: Kosteneintrag
+  label_filter_text: Filtertext
+  label_filter_value: Wert
+  label_filters: Filter
+  label_greater: '>'
+  label_is_not_project_with_subprojects: ist nicht (mit Unterprojekten)
+  label_is_project_with_subprojects: ist (mit Unterprojekten)
+  label_work_package_attributes: Attribute am Ticket
+  label_less: '<'
+  label_money: Geldwert
+  label_month_reporting: Monat der Buchung
+  label_new_report: Neue Kostenauswertung
+  label_open: Offen
+  label_operator: Operator
+  label_private_report_plural: Persönliche Kostenauswertungen
+  label_progress_bar_explanation: Kostenauswertung wird erstellt ...
+  label_public_report_plural: Gemeinsame Kostenauswertungen
+  label_really_delete_question: Diese Kostenauswertung wirklich löschen?
+  label_rows: Zeilen
+  label_saving: Speichern...
+  label_spent_on_reporting: Datum der Buchung
+  label_sum: Summe
+  label_units: Einheiten
+  label_week_reporting: Woche der Buchung
+  label_year_reporting: Jahr der Buchung
+  load_query_question: 'Die Kostenauswertung wird %{size} Tabellen-Zellen haben, was sehr rechenintensiv sein kann. Wollen Sie dennoch versuchen, die Kostenauswertung durch zu führen?'
+  permission_save_cost_reports: Speichern gemeinsamer Kostenauswertungen
+  permission_save_private_cost_reports: Speichern persönlicher Kostenauswertungen
+  project_module_reporting_module: Kostenauswertungen
+  text_costs_are_rounded_note: Die angezeigten Werte sind gerundet. Alle Berechnungen basieren auf ungerundeten Werten.
+  toggle_multiselect: Mehrfachauswahl aktivieren/deaktivieren
+  units: Einheiten
+  validation_failure_date: ist kein gültiges Datum
+  validation_failure_integer: ist keine ganze Zahl
diff --git a/spec/features/menu_spec.rb b/spec/features/menu_spec.rb
new file mode 100644
index 0000000000..61cefb8e38
--- /dev/null
+++ b/spec/features/menu_spec.rb
@@ -0,0 +1,119 @@
+#-- copyright
+# OpenProject is a project management system.
+# Copyright (C) 2012-2015 the OpenProject Foundation (OPF)
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+# See doc/COPYRIGHT.rdoc for more details.
+#++
+
+require 'spec_helper'
+
+describe 'project menu', type: :feature do
+  let(:current_user) { FactoryGirl.create :admin }
+  let!(:project) { FactoryGirl.create :valid_project, identifier: 'ponyo', name: 'Ponyo' }
+
+  before do
+    allow(User).to receive(:current).and_return current_user
+  end
+
+  ##
+  # Depending on the current page the link to the cost reports was broken.
+  # This seems to be due to a peculiarity of the rails routing where
+  # `url_for controller: :foo` would return a link relative to the controller
+  # handling the current request path if the controller was routed to via a
+  # namespaced route.
+  #
+  # Example:
+  #
+  # `url_for controller: 'cost_reports'` will yield different results ...
+  #
+  # when on `/projects/ponyo/work_packages`: `/projects/ponyo/cost_reports` (correct)
+  # when on `/projects/ponyo/work_packages/calendar`: `/work_packages/cost_reports?project_id=ponyo`
+  #
+  # This is only relevant for project menu entries, not global ones (`project_id` param is nil)*.
+  # Meaning that you have to make sure to force the absolute URL in a project menu entry
+  # by specificying the controller as e.g. '/cost_reports' instead of just 'cost_reports'.
+  #
+  # Refer to `engine.rb` to see where the menu entries are declared.
+  #
+  # * May apply to routes used with parameters in general.
+  describe '#18788 (cost reports not found (404)) regression test' do
+    describe 'link to project cost reports' do
+      shared_examples 'it leads to the project costs reports' do
+        before do
+          visit current_path
+        end
+
+        it 'leads to cost reports' do
+          click_on 'Cost Reports'
+
+          expect(page).to have_selector('.breadcrumb', text: 'HomePonyoCost Reports')
+        end
+      end
+
+      context "when on the project's activity page" do
+        let(:current_path) { '/projects/ponyo/activity' }
+
+        it_behaves_like 'it leads to the project costs reports'
+      end
+
+      context "when on the project's calendar" do
+        let(:current_path) { '/projects/ponyo/work_packages/calendar' }
+
+        it_behaves_like 'it leads to the project costs reports'
+      end
+    end
+
+    describe 'link to global cost reports', js: true do
+      shared_examples 'it leads to the cost reports' do
+        before do
+          visit current_path
+        end
+
+        it 'leads to cost reports' do
+          click_on 'Modules'
+          within '#more-menu ul' do
+            click_on 'Cost Reports'
+          end
+
+          expect(page).to have_selector('.breadcrumb', text: 'Cost Reports')
+
+          # to make sure we're not seeing the project cost reports:
+          expect(page).not_to have_text('Ponyo')
+        end
+      end
+
+      context "when on the project's activity page" do
+        let(:current_path) { '/projects/ponyo/activity' }
+
+        it_behaves_like 'it leads to the cost reports'
+      end
+
+      context "when on the project's calendar" do
+        let(:current_path) { '/projects/ponyo/work_packages/calendar' }
+
+        it_behaves_like 'it leads to the cost reports'
+      end
+    end
+  end
+end