diff --git a/.rubocop.yml b/.rubocop.yml
index aab259979..e0af6bc54 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -14,6 +14,7 @@ AllCops:
     - db/migrate/*.rb
     - node_modules/**/*
     - tmp/**/*
+    - vendor/**/*
   DisplayStyleGuide: true
   ExtraDetails: true
   TargetRubyVersion: 2.7
diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index f858c462b..10f9f1800 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -6,13 +6,13 @@ require:
 
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2020-05-22 10:44:28 +0200 using RuboCop version 0.84.0.
+# on 2020-05-28 18:37:09 +0200 using RuboCop version 0.84.0.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
 # versions of RuboCop, may require this file to be generated again.
 
-# Offense count: 268
+# Offense count: 273
 # Configuration parameters: IgnoredMethods.
 Metrics/AbcSize:
   Max: 64
@@ -40,7 +40,7 @@ RSpec/ExampleLength:
     - 'spec/models/comment_spec.rb'
     - 'spec/requests/display_ad_events_spec.rb'
 
-# Offense count: 855
+# Offense count: 866
 RSpec/MultipleExpectations:
   Max: 12
 
@@ -74,23 +74,15 @@ Rails/OutputSafety:
     - 'app/models/display_ad.rb'
     - 'app/models/message.rb'
 
-# Offense count: 17
+# Offense count: 7
 # Configuration parameters: Include.
 # Include: app/models/**/*.rb
 Rails/UniqueValidationWithoutIndex:
   Exclude:
     - 'app/models/article.rb'
-    - 'app/models/badge_achievement.rb'
-    - 'app/models/chat_channel.rb'
-    - 'app/models/chat_channel_membership.rb'
-    - 'app/models/collection.rb'
     - 'app/models/comment.rb'
-    - 'app/models/data_update_script.rb'
     - 'app/models/follow.rb'
-    - 'app/models/github_repo.rb'
     - 'app/models/notification.rb'
-    - 'app/models/organization.rb'
-    - 'app/models/response_template.rb'
 
 # Offense count: 33
 # Cop supports --auto-correct.
@@ -106,7 +98,7 @@ Style/SingleLineBlockParams:
   Exclude:
     - 'app/labor/markdown_fixer.rb'
 
-# Offense count: 534
+# Offense count: 533
 # Cop supports --auto-correct.
 # Configuration parameters: AutoCorrect, AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
 # URISchemes: http, https
diff --git a/app/liquid_tags/github_tag/github_readme_tag.rb b/app/liquid_tags/github_tag/github_readme_tag.rb
index e812b7f00..031dff499 100644
--- a/app/liquid_tags/github_tag/github_readme_tag.rb
+++ b/app/liquid_tags/github_tag/github_readme_tag.rb
@@ -41,7 +41,7 @@ class GithubTag
 
       validate_options!(*options)
 
-      path.gsub!(%r{/\z}, "") # remove optional trailing forward slash
+      path.delete_suffix!("/") # remove optional trailing forward slash
       repository_path = URI.parse(path)
       repository_path.query = repository_path.fragment = nil
 
diff --git a/spec/lib/data_update_scripts/re_index_feed_content_and_users_to_elasticsearch_spec.rb b/spec/lib/data_update_scripts/re_index_feed_content_and_users_to_elasticsearch_spec.rb
index b580d0755..4e7cf15eb 100644
--- a/spec/lib/data_update_scripts/re_index_feed_content_and_users_to_elasticsearch_spec.rb
+++ b/spec/lib/data_update_scripts/re_index_feed_content_and_users_to_elasticsearch_spec.rb
@@ -1,5 +1,4 @@
 # rubocop:disable RSpec/ExampleLength
-# rubocop:disable RSpec/MultipleExpectations
 require "rails_helper"
 require Rails.root.join("lib/data_update_scripts/20200519142908_re_index_feed_content_and_users_to_elasticsearch.rb")
 
@@ -33,4 +32,3 @@ describe DataUpdateScripts::ReIndexFeedContentAndUsersToElasticsearch do
   end
 end
 # rubocop:enable RSpec/ExampleLength
-# rubocop:enable RSpec/MultipleExpectations
diff --git a/spec/system/user/view_user_index_spec.rb b/spec/system/user/view_user_index_spec.rb
index 6acc83a34..0de22353c 100644
--- a/spec/system/user/view_user_index_spec.rb
+++ b/spec/system/user/view_user_index_spec.rb
@@ -3,7 +3,7 @@ require "rails_helper"
 RSpec.describe "User index", type: :system do
   let!(:user) { create(:user, username: "user3000") }
   let!(:article) { create(:article, user: user) }
-  let!(:other_article) { create(:article, title: rand(10000000).to_s) }
+  let!(:other_article) { create(:article, title: rand(10_000_000).to_s) }
   let!(:comment) { create(:comment, user: user, commentable: other_article) }
   let(:organization) { create(:organization) }