diff --git a/.rubocop/default.yml b/.rubocop/default.yml
index a6252d172..c130b0916 100644
--- a/.rubocop/default.yml
+++ b/.rubocop/default.yml
@@ -274,8 +274,18 @@ Style/StringConcatenation:
     - "config/routes/**/*"
 
 Style/RegexpLiteral:
+  Description: 'This cop enforces using // or %r around regular expressions.'
   EnforcedStyle: percent_r
 
+Style/RedundantBegin:
+  Description: 'This cop checks for redundant `begin` blocks.'
+  Enabled: false
+
+Rails/EnvironmentVariableAccess:
+  Description: 'This cop looks for direct access to environment variables through the ENV variable within the application code.'
+  Enabled: true
+  AllowReads: true
+
 # RSpec tests
 Style/NumericPredicate:
   Description: >-
diff --git a/Gemfile.lock b/Gemfile.lock
index 4da5cba1b..896464c7f 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -362,7 +362,7 @@ GEM
       omniauth-oauth2 (>= 1.4.0)
     openssl (2.1.2)
     parallel (1.20.1)
-    parser (3.0.0.0)
+    parser (3.0.1.1)
       ast (~> 2.4.1)
     pg (0.21.0)
     pluginator (1.5.0)
@@ -456,25 +456,25 @@ GEM
       rspec-support (~> 3.9.0)
     rspec-support (3.9.3)
     rszr (0.5.2)
-    rubocop (1.11.0)
+    rubocop (1.15.0)
       parallel (~> 1.10)
       parser (>= 3.0.0.0)
       rainbow (>= 2.2.2, < 4.0)
       regexp_parser (>= 1.8, < 3.0)
       rexml
-      rubocop-ast (>= 1.2.0, < 2.0)
+      rubocop-ast (>= 1.5.0, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 3.0)
-    rubocop-ast (1.4.1)
-      parser (>= 2.7.1.5)
-    rubocop-performance (1.10.0)
-      rubocop (>= 0.90.0, < 2.0)
+    rubocop-ast (1.6.0)
+      parser (>= 3.0.1.1)
+    rubocop-performance (1.11.3)
+      rubocop (>= 1.7.0, < 2.0)
       rubocop-ast (>= 0.4.0)
-    rubocop-rails (2.9.1)
+    rubocop-rails (2.10.1)
       activesupport (>= 4.2.0)
       rack (>= 1.1)
-      rubocop (>= 0.90.0, < 2.0)
-    rubocop-rspec (2.2.0)
+      rubocop (>= 1.7.0, < 2.0)
+    rubocop-rspec (2.3.0)
       rubocop (~> 1.0)
       rubocop-ast (>= 1.1.0)
     ruby-progressbar (1.11.0)
diff --git a/app/models/ticket/number/base.rb b/app/models/ticket/number/base.rb
index b94301808..1d5dc7b76 100644
--- a/app/models/ticket/number/base.rb
+++ b/app/models/ticket/number/base.rb
@@ -16,7 +16,7 @@ module Ticket::Number::Base
     chksum = 0
     mult   = 1
 
-    number.to_s.split('').map(&:to_i).each do |digit|
+    number.to_s.chars.map(&:to_i).each do |digit|
       chksum += digit * mult
       mult    = (mult % 3) + 1
     end
diff --git a/lib/sequencer/unit/import/common/object_attribute/sanitized_name.rb b/lib/sequencer/unit/import/common/object_attribute/sanitized_name.rb
index ab7502a75..1f79e7d43 100644
--- a/lib/sequencer/unit/import/common/object_attribute/sanitized_name.rb
+++ b/lib/sequencer/unit/import/common/object_attribute/sanitized_name.rb
@@ -40,7 +40,7 @@ class Sequencer
               # model__name
               # model_name_
               # model_name
-              downcased.split('').map { |char| char.match?(%r{[a-z0-9_]}) ? char : '_' }.join
+              downcased.chars.map { |char| char.match?(%r{[a-z0-9_]}) ? char : '_' }.join
             end
 
             def downcased
diff --git a/spec/db/migrate/issue_2019_fix_double_domain_links_in_trigger_emails_spec.rb b/spec/db/migrate/issue_2019_fix_double_domain_links_in_trigger_emails_spec.rb
index 9aa9bc8c1..f3fad3738 100644
--- a/spec/db/migrate/issue_2019_fix_double_domain_links_in_trigger_emails_spec.rb
+++ b/spec/db/migrate/issue_2019_fix_double_domain_links_in_trigger_emails_spec.rb
@@ -3,17 +3,19 @@ require 'rails_helper'
 RSpec.describe Issue2019FixDoubleDomainLinksInTriggerEmails, type: :db_migration do
   subject { create(:trigger, perform: { 'notification.email' => { 'body' => faulty_link, 'recipient' => 'customer', 'subject' => 'some subject' } }) }
 
+  # rubocop:disable Lint/InterpolationCheck
   let(:faulty_link) do
     '<a href="https://example.com/#{config.http_type}://#{config.fqdn}/#ticket/zoom/#{ticket.id}">' \
-      'View ticket' \
+    'View ticket' \
     '</a>'
   end
 
   let(:fixed_link) do
     '<a href="#{config.http_type}://#{config.fqdn}/#ticket/zoom/#{ticket.id}">' \
-      'View ticket' \
+    'View ticket' \
     '</a>'
   end
+  # rubocop:enable Lint/InterpolationCheck
 
   it "removes duplicate domains from Trigger records' notification.email bodies" do
     expect { migrate }.to change { subject.reload.perform['notification.email']['body'] }
diff --git a/spec/system/ticket/inserting_knowledge_base_answer_spec.rb b/spec/system/ticket/inserting_knowledge_base_answer_spec.rb
index 38975b3fb..4a212609c 100644
--- a/spec/system/ticket/inserting_knowledge_base_answer_spec.rb
+++ b/spec/system/ticket/inserting_knowledge_base_answer_spec.rb
@@ -61,7 +61,7 @@ RSpec.describe 'inserting Knowledge Base answer', type: :system, authenticated_a
 
   def insert_kb_answer(translation, target_field)
     target_field.send_keys('??')
-    translation.title.slice(0, 3).split('').each { |letter| target_field.send_keys(letter) }
+    translation.title.slice(0, 3).chars.each { |letter| target_field.send_keys(letter) }
 
     find(:text_module, translation.id).click
   end
diff --git a/test/browser_test_helper.rb b/test/browser_test_helper.rb
index 8a848e91f..6795eb87a 100644
--- a/test/browser_test_helper.rb
+++ b/test/browser_test_helper.rb
@@ -786,7 +786,7 @@ class TestCase < ActiveSupport::TestCase
     begin
       if params[:slow]
         element.send_keys('')
-        keys = params[:value].to_s.split('')
+        keys = params[:value].to_s.chars
         keys.each do |key|
           instance.action.send_keys(key).perform
         end
@@ -803,7 +803,7 @@ class TestCase < ActiveSupport::TestCase
 
       if params[:slow]
         element.send_keys('')
-        keys = params[:value].to_s.split('')
+        keys = params[:value].to_s.chars
         keys.each do |key|
           instance.action.send_keys(key).perform
         end