diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index e48cbcaba..114509d29 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1753,6 +1753,7 @@ Style/SoleNestedConditional:
     - 'app/models/version.rb'
     - 'app/models/watcher.rb'
     - 'app/models/wiki_page.rb'
+    - 'app/models/wiki_annotate.rb'
     - 'lib/redmine/core_ext/active_record.rb'
 
 # Cop supports --auto-correct.
diff --git a/app/models/anonymous_user.rb b/app/models/anonymous_user.rb
new file mode 100644
index 000000000..d1b215b8e
--- /dev/null
+++ b/app/models/anonymous_user.rb
@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+# Redmine - project management software
+# Copyright (C) 2006-2021  Jean-Philippe Lang
+#
+# 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.
+
+class AnonymousUser < User
+  validate :validate_anonymous_uniqueness, :on => :create
+
+  self.valid_statuses = [STATUS_ANONYMOUS]
+
+  def validate_anonymous_uniqueness
+    # There should be only one AnonymousUser in the database
+    errors.add :base, 'An anonymous user already exists.' if AnonymousUser.unscoped.exists?
+  end
+
+  def available_custom_fields
+    []
+  end
+
+  # Overrides a few properties
+  def logged?; false end
+  def admin; false end
+  def name(*args); I18n.t(:label_user_anonymous) end
+  def mail=(*args); nil end
+  def mail; nil end
+  def time_zone; nil end
+  def rss_key; nil end
+
+  def pref
+    UserPreference.new(:user => self)
+  end
+
+  # Returns the user's bult-in role
+  def builtin_role
+    @builtin_role ||= Role.anonymous
+  end
+
+  def membership(*args)
+    nil
+  end
+
+  def member_of?(*args)
+    false
+  end
+
+  # Anonymous user can not be destroyed
+  def destroy
+    false
+  end
+
+  protected
+
+  def instantiate_email_address
+  end
+end
diff --git a/app/models/user.rb b/app/models/user.rb
index cb0ad9e3a..681829265 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -999,54 +999,3 @@ class User < Principal
     end
   end
 end
-
-class AnonymousUser < User
-  validate :validate_anonymous_uniqueness, :on => :create
-
-  self.valid_statuses = [STATUS_ANONYMOUS]
-
-  def validate_anonymous_uniqueness
-    # There should be only one AnonymousUser in the database
-    errors.add :base, 'An anonymous user already exists.' if AnonymousUser.unscoped.exists?
-  end
-
-  def available_custom_fields
-    []
-  end
-
-  # Overrides a few properties
-  def logged?; false end
-  def admin; false end
-  def name(*args); I18n.t(:label_user_anonymous) end
-  def mail=(*args); nil end
-  def mail; nil end
-  def time_zone; nil end
-  def rss_key; nil end
-
-  def pref
-    UserPreference.new(:user => self)
-  end
-
-  # Returns the user's bult-in role
-  def builtin_role
-    @builtin_role ||= Role.anonymous
-  end
-
-  def membership(*args)
-    nil
-  end
-
-  def member_of?(*args)
-    false
-  end
-
-  # Anonymous user can not be destroyed
-  def destroy
-    false
-  end
-
-  protected
-
-  def instantiate_email_address
-  end
-end
diff --git a/app/models/wiki_annotate.rb b/app/models/wiki_annotate.rb
new file mode 100644
index 000000000..c0411e3a6
--- /dev/null
+++ b/app/models/wiki_annotate.rb
@@ -0,0 +1,58 @@
+# frozen_string_literal: true
+
+# Redmine - project management software
+# Copyright (C) 2006-2021  Jean-Philippe Lang
+#
+# 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.
+
+class WikiAnnotate
+  attr_reader :lines, :content
+
+  def initialize(content)
+    @content = content
+    current = content
+    current_lines = current.text.split(/\r?\n/)
+    @lines = current_lines.collect {|t| [nil, nil, t]}
+    positions = []
+    current_lines.size.times {|i| positions << i}
+    while current.previous
+      d = current.previous.text.split(/\r?\n/).diff(current.text.split(/\r?\n/)).diffs.flatten
+      d.each_slice(3) do |s|
+        sign, line = s[0], s[1]
+        if sign == '+' && positions[line] && positions[line] != -1
+          if @lines[positions[line]][0].nil?
+            @lines[positions[line]][0] = current.version
+            @lines[positions[line]][1] = current.author
+          end
+        end
+        if sign == '-'
+          positions.insert(line, -1)
+        else
+          positions[line] = nil
+        end
+      end
+      positions.compact!
+      # Stop if every line is annotated
+      break unless @lines.detect {|line| line[0].nil?}
+
+      current = current.previous
+    end
+    @lines.each do |line|
+      line[0] ||= current.version
+      # if the last known version is > 1 (eg. history was cleared), we don't know the author
+      line[1] ||= current.author if current.version == 1
+    end
+  end
+end
diff --git a/app/models/wiki_diff.rb b/app/models/wiki_diff.rb
new file mode 100644
index 000000000..00d35bb0b
--- /dev/null
+++ b/app/models/wiki_diff.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+# Redmine - project management software
+# Copyright (C) 2006-2021  Jean-Philippe Lang
+#
+# 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.
+
+class WikiDiff < Redmine::Helpers::Diff
+  attr_reader :content_to, :content_from
+
+  def initialize(content_to, content_from)
+    @content_to = content_to
+    @content_from = content_from
+    super(content_to.text, content_from.text)
+  end
+end
diff --git a/app/models/wiki_page.rb b/app/models/wiki_page.rb
index e6acd0f76..2e76e076e 100644
--- a/app/models/wiki_page.rb
+++ b/app/models/wiki_page.rb
@@ -290,53 +290,3 @@ class WikiPage < ActiveRecord::Base
     (association(:content).loaded? ? content : content_without_text).try(name)
   end
 end
-
-class WikiDiff < Redmine::Helpers::Diff
-  attr_reader :content_to, :content_from
-
-  def initialize(content_to, content_from)
-    @content_to = content_to
-    @content_from = content_from
-    super(content_to.text, content_from.text)
-  end
-end
-
-class WikiAnnotate
-  attr_reader :lines, :content
-
-  def initialize(content)
-    @content = content
-    current = content
-    current_lines = current.text.split(/\r?\n/)
-    @lines = current_lines.collect {|t| [nil, nil, t]}
-    positions = []
-    current_lines.size.times {|i| positions << i}
-    while current.previous
-      d = current.previous.text.split(/\r?\n/).diff(current.text.split(/\r?\n/)).diffs.flatten
-      d.each_slice(3) do |s|
-        sign, line = s[0], s[1]
-        if sign == '+' && positions[line] && positions[line] != -1
-          if @lines[positions[line]][0].nil?
-            @lines[positions[line]][0] = current.version
-            @lines[positions[line]][1] = current.author
-          end
-        end
-        if sign == '-'
-          positions.insert(line, -1)
-        else
-          positions[line] = nil
-        end
-      end
-      positions.compact!
-      # Stop if every line is annotated
-      break unless @lines.detect {|line| line[0].nil?}
-
-      current = current.previous
-    end
-    @lines.each do |line|
-      line[0] ||= current.version
-      # if the last known version is > 1 (eg. history was cleared), we don't know the author
-      line[1] ||= current.author if current.version == 1
-    end
-  end
-end
diff --git a/lib/redmine.rb b/lib/redmine.rb
index 5721667d8..b018779a7 100644
--- a/lib/redmine.rb
+++ b/lib/redmine.rb
@@ -58,8 +58,10 @@ require 'redmine/thumbnail'
 require 'redmine/unified_diff'
 require 'redmine/utils'
 require 'redmine/version'
+require 'redmine/wiki_formatting/links_helper'
 require 'redmine/wiki_formatting'
 
+
 require 'redmine/default_data/loader'
 require 'redmine/helpers/calendar'
 require 'redmine/helpers/diff'
diff --git a/lib/redmine/wiki_formatting.rb b/lib/redmine/wiki_formatting.rb
index 99058462b..471082edc 100644
--- a/lib/redmine/wiki_formatting.rb
+++ b/lib/redmine/wiki_formatting.rb
@@ -115,89 +115,6 @@ module Redmine
       end
     end
 
-    module LinksHelper
-      AUTO_LINK_RE = %r{
-                      (                          # leading text
-                        <\w+[^>]*?>|             # leading HTML tag, or
-                        [\s\(\[,;]|              # leading punctuation, or
-                        ^                        # beginning of line
-                      )
-                      (
-                        (?:https?://)|           # protocol spec, or
-                        (?:s?ftps?://)|
-                        (?:www\.)                # www.*
-                      )
-                      (
-                        ([^<]\S*?)               # url
-                        (\/)?                    # slash
-                      )
-                      ((?:&gt;)?|[^[:alnum:]_\=\/;\(\)\-]*?)             # post
-                      (?=<|\s|$)
-                     }x unless const_defined?(:AUTO_LINK_RE)
-
-      # Destructively replaces urls into clickable links
-      def auto_link!(text)
-        text.gsub!(AUTO_LINK_RE) do
-          all, leading, proto, url, post = $&, $1, $2, $3, $6
-          if /<a\s/i.match?(leading) || /![<>=]?/.match?(leading)
-            # don't replace URLs that are already linked
-            # and URLs prefixed with ! !> !< != (textile images)
-            all
-          else
-            # Idea below : an URL with unbalanced parenthesis and
-            # ending by ')' is put into external parenthesis
-            if url[-1] == ")" and ((url.count("(") - url.count(")")) < 0)
-              url = url[0..-2] # discard closing parenthesis from url
-              post = ")" + post # add closing parenthesis to post
-            end
-            content = proto + url
-            href = "#{proto=="www."?"http://www.":proto}#{url}"
-            %(#{leading}<a class="external" href="#{ERB::Util.html_escape href}">#{ERB::Util.html_escape content}</a>#{post}).html_safe
-          end
-        end
-      end
-
-      # Destructively replaces email addresses into clickable links
-      def auto_mailto!(text)
-        text.gsub!(/([\w\.!#\$%\-+.\/]+@[A-Za-z0-9\-]+(\.[A-Za-z0-9\-]+)+)/) do
-          mail = $1
-          if /<a\b[^>]*>(.*)(#{Regexp.escape(mail)})(.*)<\/a>/.match?(text)
-            mail
-          else
-            %(<a class="email" href="mailto:#{ERB::Util.html_escape mail}">#{ERB::Util.html_escape mail}</a>).html_safe
-          end
-        end
-      end
-
-      def restore_redmine_links(html)
-        # restore wiki links eg. [[Foo]]
-        html.gsub!(%r{\[<a href="(.*?)">(.*?)</a>\]}) do
-          "[[#{$2}]]"
-        end
-        # restore Redmine links with double-quotes, eg. version:"1.0"
-        html.gsub!(/(\w):&quot;(.+?)&quot;/) do
-          "#{$1}:\"#{$2}\""
-        end
-        # restore user links with @ in login name eg. [@jsmith@somenet.foo]
-        html.gsub!(%r{[@\A]<a(\sclass="email")? href="mailto:(.*?)">(.*?)</a>}) do
-          "@#{$2}"
-        end
-        # restore user links with @ in login name eg. [user:jsmith@somenet.foo]
-        html.gsub!(%r{\buser:<a(\sclass="email")? href="mailto:(.*?)">(.*?)<\/a>}) do
-          "user:#{$2}"
-        end
-        # restore attachments links with @ in file name eg. [attachment:image@2x.png]
-        html.gsub!(%r{\battachment:<a(\sclass="email")? href="mailto:(.*?)">(.*?)</a>}) do
-          "attachment:#{$2}"
-        end
-        # restore hires images which are misrecognized as email address eg. [printscreen@2x.png]
-        html.gsub!(%r{<a(\sclass="email")? href="mailto:[^"]+@\dx\.(bmp|gif|jpg|jpe|jpeg|png)">(.*?)</a>}) do
-          "#{$3}"
-        end
-        html
-      end
-    end
-
     # Default formatter module
     module NullFormatter
       class Formatter
diff --git a/lib/redmine/wiki_formatting/links_helper.rb b/lib/redmine/wiki_formatting/links_helper.rb
new file mode 100644
index 000000000..2e057df3e
--- /dev/null
+++ b/lib/redmine/wiki_formatting/links_helper.rb
@@ -0,0 +1,107 @@
+# frozen_string_literal: true
+
+# Redmine - project management software
+# Copyright (C) 2006-2021  Jean-Philippe Lang
+#
+# 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.
+
+require 'loofah/helpers'
+
+module Redmine
+  module WikiFormatting
+    module LinksHelper
+      AUTO_LINK_RE = %r{
+                      (                          # leading text
+                        <\w+[^>]*?>|             # leading HTML tag, or
+                        [\s\(\[,;]|              # leading punctuation, or
+                        ^                        # beginning of line
+                      )
+                      (
+                        (?:https?://)|           # protocol spec, or
+                        (?:s?ftps?://)|
+                        (?:www\.)                # www.*
+                      )
+                      (
+                        ([^<]\S*?)               # url
+                        (\/)?                    # slash
+                      )
+                      ((?:&gt;)?|[^[:alnum:]_\=\/;\(\)\-]*?)             # post
+                      (?=<|\s|$)
+                     }x unless const_defined?(:AUTO_LINK_RE)
+
+      # Destructively replaces urls into clickable links
+      def auto_link!(text)
+        text.gsub!(AUTO_LINK_RE) do
+          all, leading, proto, url, post = $&, $1, $2, $3, $6
+          if /<a\s/i.match?(leading) || /![<>=]?/.match?(leading)
+            # don't replace URLs that are already linked
+            # and URLs prefixed with ! !> !< != (textile images)
+            all
+          else
+            # Idea below : an URL with unbalanced parenthesis and
+            # ending by ')' is put into external parenthesis
+            if url[-1] == ")" and ((url.count("(") - url.count(")")) < 0)
+              url = url[0..-2] # discard closing parenthesis from url
+              post = ")" + post # add closing parenthesis to post
+            end
+            content = proto + url
+            href = "#{proto=="www."?"http://www.":proto}#{url}"
+            %(#{leading}<a class="external" href="#{ERB::Util.html_escape href}">#{ERB::Util.html_escape content}</a>#{post}).html_safe
+          end
+        end
+      end
+
+      # Destructively replaces email addresses into clickable links
+      def auto_mailto!(text)
+        text.gsub!(/([\w\.!#\$%\-+.\/]+@[A-Za-z0-9\-]+(\.[A-Za-z0-9\-]+)+)/) do
+          mail = $1
+          if /<a\b[^>]*>(.*)(#{Regexp.escape(mail)})(.*)<\/a>/.match?(text)
+            mail
+          else
+            %(<a class="email" href="mailto:#{ERB::Util.html_escape mail}">#{ERB::Util.html_escape mail}</a>).html_safe
+          end
+        end
+      end
+
+      def restore_redmine_links(html)
+        # restore wiki links eg. [[Foo]]
+        html.gsub!(%r{\[<a href="(.*?)">(.*?)</a>\]}) do
+          "[[#{$2}]]"
+        end
+        # restore Redmine links with double-quotes, eg. version:"1.0"
+        html.gsub!(/(\w):&quot;(.+?)&quot;/) do
+          "#{$1}:\"#{$2}\""
+        end
+        # restore user links with @ in login name eg. [@jsmith@somenet.foo]
+        html.gsub!(%r{[@\A]<a(\sclass="email")? href="mailto:(.*?)">(.*?)</a>}) do
+          "@#{$2}"
+        end
+        # restore user links with @ in login name eg. [user:jsmith@somenet.foo]
+        html.gsub!(%r{\buser:<a(\sclass="email")? href="mailto:(.*?)">(.*?)<\/a>}) do
+          "user:#{$2}"
+        end
+        # restore attachments links with @ in file name eg. [attachment:image@2x.png]
+        html.gsub!(%r{\battachment:<a(\sclass="email")? href="mailto:(.*?)">(.*?)</a>}) do
+          "attachment:#{$2}"
+        end
+        # restore hires images which are misrecognized as email address eg. [printscreen@2x.png]
+        html.gsub!(%r{<a(\sclass="email")? href="mailto:[^"]+@\dx\.(bmp|gif|jpg|jpe|jpeg|png)">(.*?)</a>}) do
+          "#{$3}"
+        end
+        html
+      end
+    end
+  end
+end