diff --git a/.gitlab/ci/frontend.gitlab-ci.yml b/.gitlab/ci/frontend.gitlab-ci.yml
index 2eda2f6ab9d..9c494fd53bb 100644
--- a/.gitlab/ci/frontend.gitlab-ci.yml
+++ b/.gitlab/ci/frontend.gitlab-ci.yml
@@ -367,6 +367,7 @@ jest-with-fixtures vue3 mr:
     when: always
     paths:
       - junit_jest.xml
+  parallel: 1
   script:
     - run_timed_command "yarn jest:ci:vue3-mr:with-fixtures"
 
diff --git a/GITLAB_SHELL_VERSION b/GITLAB_SHELL_VERSION
index 288cc1f2838..9d68c6c43b5 100644
--- a/GITLAB_SHELL_VERSION
+++ b/GITLAB_SHELL_VERSION
@@ -1 +1 @@
-14.38.0
+14.39.0
diff --git a/app/assets/stylesheets/pages/issues.scss b/app/assets/stylesheets/pages/issues.scss
index 0ff994af59b..dd4faee1eee 100644
--- a/app/assets/stylesheets/pages/issues.scss
+++ b/app/assets/stylesheets/pages/issues.scss
@@ -237,6 +237,7 @@ ul.related-merge-requests > li gl-emoji {
   right: var(--application-bar-right);
   width: auto;
   top: $calc-application-header-height;
+  max-width: calc(100vw - #{$super-sidebar-width});
 }
 
 .limit-container-width {
diff --git a/app/models/concerns/linkable_item.rb b/app/models/concerns/linkable_item.rb
index c91e3615ba7..ab8a6d8bb54 100644
--- a/app/models/concerns/linkable_item.rb
+++ b/app/models/concerns/linkable_item.rb
@@ -12,7 +12,7 @@ module LinkableItem
   include IssuableLink
 
   included do
-    validate :check_existing_parent_link
+    validate :check_existing_parent_link, on: :create
 
     scope :for_source, ->(item) { where(source_id: item.id) }
     scope :for_target, ->(item) { where(target_id: item.id) }
diff --git a/app/models/work_items/parent_link.rb b/app/models/work_items/parent_link.rb
index 545244e52d5..e0a2a3fca75 100644
--- a/app/models/work_items/parent_link.rb
+++ b/app/models/work_items/parent_link.rb
@@ -17,7 +17,7 @@ module WorkItems
     validate :validate_cyclic_reference
     validate :validate_max_children
     validate :validate_confidentiality
-    validate :check_existing_related_link
+    validate :check_existing_related_link, on: :create
 
     scope :for_parents, ->(parent_ids) { where(work_item_parent_id: parent_ids) }
     scope :for_children, ->(children_ids) { where(work_item: children_ids) }
diff --git a/config/initializers/active_job_shard_support.rb b/config/initializers/active_job_shard_support.rb
index ef1f86bfbf0..865df48c651 100644
--- a/config/initializers/active_job_shard_support.rb
+++ b/config/initializers/active_job_shard_support.rb
@@ -1,10 +1,9 @@
 # frozen_string_literal: true
 
-# As discussed in https://gitlab.com/gitlab-org/gitlab/-/merge_requests/148637#note_1850247875,
-# Rails 7.1 introduces enqueue_all which is not covered in this patch.
 # We deliver emails using the `deliver_later` method and it uses ActiveJob
 # under the hood, which later processes the email via the defined ActiveJob adapter's `enqueue` method.
 # For GitLab, the ActiveJob adapter is Sidekiq (in development and production environments).
+#
 # We need to set the following up to override the ActiveJob adapater
 # so as to ensure that mailer jobs are enqueued in a shard-aware manner.
 
@@ -15,8 +14,18 @@ end
 module ActiveJob
   module QueueAdapters
     module ActiveJobShardSupport
+      if ::Gitlab.next_rails?
+        def enqueue_all(jobs)
+          Gitlab::SidekiqSharding::Router.route(ActionMailer::MailDeliveryJob) do
+            super(jobs)
+          end
+        end
+      end
+
       %i[enqueue enqueue_at].each do |name|
         define_method(name) do |*args|
+          return super(*args) if ::Gitlab.next_rails?
+
           Gitlab::SidekiqSharding::Router.route(ActionMailer::MailDeliveryJob) do
             super(*args)
           end
diff --git a/doc/tutorials/observability/img/django_metrics.png b/doc/tutorials/observability/img/django_metrics.png
index aa90b039d1e..c2a662bfe73 100644
Binary files a/doc/tutorials/observability/img/django_metrics.png and b/doc/tutorials/observability/img/django_metrics.png differ
diff --git a/doc/tutorials/observability/img/django_traces.png b/doc/tutorials/observability/img/django_traces.png
index 4bbc064ba8e..6d3bf1b226a 100644
Binary files a/doc/tutorials/observability/img/django_traces.png and b/doc/tutorials/observability/img/django_traces.png differ
diff --git a/doc/tutorials/observability/img/java_configuration_menu.png b/doc/tutorials/observability/img/java_configuration_menu.png
index 8f301aa9054..1fedf0411b6 100644
Binary files a/doc/tutorials/observability/img/java_configuration_menu.png and b/doc/tutorials/observability/img/java_configuration_menu.png differ
diff --git a/doc/tutorials/observability/img/java_edit_configuration.png b/doc/tutorials/observability/img/java_edit_configuration.png
index 4b067af302e..c043fc4ee16 100644
Binary files a/doc/tutorials/observability/img/java_edit_configuration.png and b/doc/tutorials/observability/img/java_edit_configuration.png differ
diff --git a/doc/tutorials/observability/img/maven_changes.png b/doc/tutorials/observability/img/maven_changes.png
index 7f094a70af7..1ac2d7a5d04 100644
Binary files a/doc/tutorials/observability/img/maven_changes.png and b/doc/tutorials/observability/img/maven_changes.png differ
diff --git a/doc/user/application_security/vulnerabilities/img/example_code_flow_of_python_applications_v17_3.png b/doc/user/application_security/vulnerabilities/img/example_code_flow_of_python_applications_v17_3.png
index c2880d6154c..fea66a95699 100644
Binary files a/doc/user/application_security/vulnerabilities/img/example_code_flow_of_python_applications_v17_3.png and b/doc/user/application_security/vulnerabilities/img/example_code_flow_of_python_applications_v17_3.png differ
diff --git a/doc/user/infrastructure/clusters/connect/img/variables_civo.png b/doc/user/infrastructure/clusters/connect/img/variables_civo.png
index acbe4f60df6..4a47c944c56 100644
Binary files a/doc/user/infrastructure/clusters/connect/img/variables_civo.png and b/doc/user/infrastructure/clusters/connect/img/variables_civo.png differ
diff --git a/doc/user/project/img/issue_boards_blocked_icon_v17_3.png b/doc/user/project/img/issue_boards_blocked_icon_v17_3.png
index 5023c9afa13..f5cb789c15e 100644
Binary files a/doc/user/project/img/issue_boards_blocked_icon_v17_3.png and b/doc/user/project/img/issue_boards_blocked_icon_v17_3.png differ
diff --git a/doc/user/project/merge_requests/img/status_checks_create_form_v14_0.png b/doc/user/project/merge_requests/img/status_checks_create_form_v14_0.png
index b9c0f85ca79..9f652fe9e6a 100644
Binary files a/doc/user/project/merge_requests/img/status_checks_create_form_v14_0.png and b/doc/user/project/merge_requests/img/status_checks_create_form_v14_0.png differ
diff --git a/doc/user/project/merge_requests/img/status_checks_list_view_v14_0.png b/doc/user/project/merge_requests/img/status_checks_list_view_v14_0.png
index ade983ef129..c39628b1464 100644
Binary files a/doc/user/project/merge_requests/img/status_checks_list_view_v14_0.png and b/doc/user/project/merge_requests/img/status_checks_list_view_v14_0.png differ
diff --git a/doc/user/project/merge_requests/img/status_checks_update_form_v14_0.png b/doc/user/project/merge_requests/img/status_checks_update_form_v14_0.png
index da849e3d6b8..31d33ce511b 100644
Binary files a/doc/user/project/merge_requests/img/status_checks_update_form_v14_0.png and b/doc/user/project/merge_requests/img/status_checks_update_form_v14_0.png differ
diff --git a/lib/gitlab/patch/sidekiq_job_setter.rb b/lib/gitlab/patch/sidekiq_job_setter.rb
index a9e0a56240c..b5f80c9884f 100644
--- a/lib/gitlab/patch/sidekiq_job_setter.rb
+++ b/lib/gitlab/patch/sidekiq_job_setter.rb
@@ -11,7 +11,25 @@ module Gitlab
       # so we only need to patch 1 method.
       def perform_async(*args)
         # rubocop:disable Gitlab/ModuleWithInstanceVariables -- @klass is present in the class we are patching
-        Gitlab::SidekiqSharding::Router.route(@klass) do
+
+        route_with_klass = @klass
+
+        # If an ActiveJob JobWrapper is pushed, check the arg hash's job_class for routing decisions.
+        #
+        # See https://github.com/rails/rails/blob/v7.1.0/activejob/lib/active_job/queue_adapters/sidekiq_adapter.rb#L21
+        # `job.serialize` would return a hash containing `job_class` set in
+        # https://github.com/rails/rails/blob/v7.1.0/activejob/lib/active_job/core.rb#L110
+        #
+        # In the GitLab Rails application, this only applies to ActionMailer::MailDeliveryJob
+        # but routing using the `job_class` keeps the option of using ActiveJob available for us.
+        #
+        if @klass == ActiveJob::QueueAdapters::SidekiqAdapter::JobWrapper &&
+            args.first.is_a?(Hash) &&
+            args.first['job_class']
+          route_with_klass = args.first['job_class'].to_s.safe_constantize
+        end
+
+        Gitlab::SidekiqSharding::Router.route(route_with_klass) do
           # rubocop:enable Gitlab/ModuleWithInstanceVariables
           super
         end
diff --git a/lib/tasks/gitlab/shell.rake b/lib/tasks/gitlab/shell.rake
index 5eb3ff8c28b..2bb14504d32 100644
--- a/lib/tasks/gitlab/shell.rake
+++ b/lib/tasks/gitlab/shell.rake
@@ -30,8 +30,7 @@ namespace :gitlab do
         File.open("config.yml", "w+") { |f| f.puts config.to_yaml }
 
         [
-          %w[bin/install],
-          %w[make build]
+          %w[make make_necessary_dirs build]
         ].each do |cmd|
           unless Kernel.system(*cmd)
             raise "command failed: #{cmd.join(' ')}"
diff --git a/package.json b/package.json
index ed9710d4e6a..9104440c195 100644
--- a/package.json
+++ b/package.json
@@ -249,7 +249,7 @@
     "yaml": "^2.0.0-10"
   },
   "devDependencies": {
-    "@gitlab/eslint-plugin": "19.6.1",
+    "@gitlab/eslint-plugin": "20.0.0",
     "@gitlab/stylelint-config": "6.2.1",
     "@graphql-eslint/eslint-plugin": "3.20.1",
     "@originjs/vite-plugin-commonjs": "^1.0.3",
diff --git a/spec/models/work_items/parent_link_spec.rb b/spec/models/work_items/parent_link_spec.rb
index b53717f815e..6ce49c0bac1 100644
--- a/spec/models/work_items/parent_link_spec.rb
+++ b/spec/models/work_items/parent_link_spec.rb
@@ -168,6 +168,66 @@ RSpec.describe WorkItems::ParentLink, feature_category: :portfolio_management do
         end
       end
 
+      context 'when parent is already linked' do
+        shared_examples 'invalid link' do |link_factory|
+          let_it_be(:parent_link) { build(:parent_link, work_item_parent: issue, work_item: task1) }
+          let(:error_msg) { 'cannot assign a linked work item as a parent' }
+
+          context 'when creating new link' do
+            context 'when parent is the link target' do
+              before do
+                create(link_factory, source_id: task1.id, target_id: issue.id)
+              end
+
+              it do
+                expect(parent_link).not_to be_valid
+                expect(parent_link.errors[:work_item]).to include(error_msg)
+              end
+            end
+
+            context 'when parent is the link source' do
+              before do
+                create(link_factory, source_id: issue.id, target_id: task1.id)
+              end
+
+              it do
+                expect(parent_link).not_to be_valid
+                expect(parent_link.errors[:work_item]).to include(error_msg)
+              end
+            end
+          end
+
+          context 'when updating existing link' do
+            context 'when parent is the link target' do
+              before do
+                create(link_factory, source_id: task1.id, target_id: issue.id)
+                parent_link.save!(validate: false)
+              end
+
+              it do
+                expect(parent_link).to be_valid
+                expect(parent_link.errors[:work_item]).not_to include(error_msg)
+              end
+            end
+
+            context 'when parent is the link source' do
+              before do
+                create(link_factory, source_id: issue.id, target_id: task1.id)
+                parent_link.save!(validate: false)
+              end
+
+              it do
+                expect(parent_link).to be_valid
+                expect(parent_link.errors[:work_item]).not_to include(error_msg)
+              end
+            end
+          end
+        end
+
+        it_behaves_like 'invalid link', :work_item_link
+        it_behaves_like 'invalid link', :issue_link
+      end
+
       context 'when setting confidentiality' do
         using RSpec::Parameterized::TableSyntax
 
@@ -191,38 +251,6 @@ RSpec.describe WorkItems::ParentLink, feature_category: :portfolio_management do
           end
         end
       end
-
-      context 'when parent is already linked' do
-        shared_examples 'invalid link' do |link_factory|
-          let_it_be(:parent_link) { build(:parent_link, work_item_parent: issue, work_item: task1) }
-          let(:error_msg) { 'cannot assign a linked work item as a parent' }
-
-          context 'when parent is the link target' do
-            before do
-              create(link_factory, source_id: task1.id, target_id: issue.id)
-            end
-
-            it do
-              expect(parent_link).not_to be_valid
-              expect(parent_link.errors[:work_item]).to include(error_msg)
-            end
-          end
-
-          context 'when parent is the link source' do
-            before do
-              create(link_factory, source_id: issue.id, target_id: task1.id)
-            end
-
-            it do
-              expect(parent_link).not_to be_valid
-              expect(parent_link.errors[:work_item]).to include(error_msg)
-            end
-          end
-        end
-
-        it_behaves_like 'invalid link', :work_item_link
-        it_behaves_like 'invalid link', :issue_link
-      end
     end
   end
 
diff --git a/spec/support/shared_examples/models/concerns/linkable_items_shared_examples.rb b/spec/support/shared_examples/models/concerns/linkable_items_shared_examples.rb
index eb37fe66c11..9720c997aa2 100644
--- a/spec/support/shared_examples/models/concerns/linkable_items_shared_examples.rb
+++ b/spec/support/shared_examples/models/concerns/linkable_items_shared_examples.rb
@@ -8,34 +8,65 @@ RSpec.shared_examples 'includes LinkableItem concern' do
     subject(:link) { build(link_factory, source_id: source.id, target_id: target.id) }
 
     describe '#check_existing_parent_link' do
-      shared_examples 'invalid due to existing link' do
-        it do
-          is_expected.to be_invalid
-          expect(link.errors.messages[:source]).to include("is a parent or child of this #{item_type}")
+      context 'for new issuable link' do
+        shared_examples 'invalid due to existing link' do
+          it do
+            is_expected.to be_invalid
+            expect(link.errors.messages[:source]).to include("is a parent or child of this #{item_type}")
+          end
         end
-      end
 
-      context 'without existing link parent' do
-        let(:source) { issue }
-        let(:target) { task }
-
-        it 'is valid' do
-          is_expected.to be_valid
-          expect(link.errors).to be_empty
-        end
-      end
-
-      context 'with existing link parent' do
-        let_it_be(:relationship) { create(:parent_link, work_item_parent: issue, work_item: task) }
-
-        it_behaves_like 'invalid due to existing link' do
+        context 'without existing link parent' do
           let(:source) { issue }
           let(:target) { task }
+
+          it 'is valid' do
+            is_expected.to be_valid
+            expect(link.errors).to be_empty
+          end
         end
 
-        it_behaves_like 'invalid due to existing link' do
+        context 'with existing link parent' do
+          let_it_be(:relationship) { create(:parent_link, work_item_parent: issue, work_item: task) }
+
+          it_behaves_like 'invalid due to existing link' do
+            let(:source) { issue }
+            let(:target) { task }
+          end
+
+          it_behaves_like 'invalid due to existing link' do
+            let(:source) { task }
+            let(:target) { issue }
+          end
+        end
+      end
+
+      context 'for existing issuable link with existing parent link' do
+        let(:link) { build(link_factory, source_id: source.id, target_id: target.id) }
+
+        before do
+          create(:parent_link, work_item_parent: issue, work_item: task)
+          link.save!(validate: false)
+        end
+
+        context 'when source is issue' do
+          let(:source) { issue }
+          let(:target) { task }
+
+          it 'is valid' do
+            expect(link).to be_valid
+            expect(link.errors).to be_empty
+          end
+        end
+
+        context 'when source is task' do
           let(:source) { task }
           let(:target) { issue }
+
+          it 'is valid' do
+            expect(link).to be_valid
+            expect(link.errors).to be_empty
+          end
         end
       end
     end
diff --git a/spec/tasks/gitlab/shell_rake_spec.rb b/spec/tasks/gitlab/shell_rake_spec.rb
index 4ca46a9ce40..5fb85a526b6 100644
--- a/spec/tasks/gitlab/shell_rake_spec.rb
+++ b/spec/tasks/gitlab/shell_rake_spec.rb
@@ -12,8 +12,7 @@ RSpec.describe 'gitlab:shell rake tasks', :silence_stdout do
   describe 'install task' do
     it 'installs and compiles gitlab-shell' do
       expect_any_instance_of(Gitlab::TaskHelpers).to receive(:checkout_or_clone_version)
-      allow(Kernel).to receive(:system).with('bin/install').and_return(true)
-      allow(Kernel).to receive(:system).with('make', 'build').and_return(true)
+      allow(Kernel).to receive(:system).with('make', 'make_necessary_dirs', 'build').and_return(true)
 
       run_rake_task('gitlab:shell:install')
     end
diff --git a/spec/workers/concerns/application_worker_spec.rb b/spec/workers/concerns/application_worker_spec.rb
index ade4c4b4f26..d41dd1dc2eb 100644
--- a/spec/workers/concerns/application_worker_spec.rb
+++ b/spec/workers/concerns/application_worker_spec.rb
@@ -652,6 +652,46 @@ RSpec.describe ApplicationWorker, feature_category: :shared do
       end
     end
 
+    context 'with ActiveJob::QueueAdapters::SidekiqAdapter::JobWrapper' do
+      let(:worker) { ActiveJob::QueueAdapters::SidekiqAdapter::JobWrapper }
+
+      context 'when calling perform_async with setter' do
+        subject(:operation) { worker.set(testing: true).perform_async({ 'job_class' => ActionMailer::MailDeliveryJob }) }
+
+        it_behaves_like 'uses shard router'
+      end
+
+      context 'when calling perform_async with setter without job_class' do
+        subject(:operation) { worker.set(testing: true).perform_async }
+
+        it_behaves_like 'uses shard router'
+      end
+
+      context 'when calling perform_in with setter' do
+        subject(:operation) { worker.set(testing: true).perform_in(1, { 'job_class' => ActionMailer::MailDeliveryJob }) }
+
+        it_behaves_like 'uses shard router'
+      end
+
+      context 'when calling perform_in with setter without job_class' do
+        subject(:operation) { worker.set(testing: true).perform_in(1) }
+
+        it_behaves_like 'uses shard router'
+      end
+
+      context 'when calling perform_at with setter' do
+        subject(:operation) { worker.set(testing: true).perform_at(1, { 'job_class' => ActionMailer::MailDeliveryJob }) }
+
+        it_behaves_like 'uses shard router'
+      end
+
+      context 'when calling perform_at with setter without job_class' do
+        subject(:operation) { worker.set(testing: true).perform_at(1) }
+
+        it_behaves_like 'uses shard router'
+      end
+    end
+
     context 'when calling perform_async with setter' do
       subject(:operation) { worker.set(testing: true).perform_async }
 
diff --git a/yarn.lock b/yarn.lock
index 86007442c21..df3d85a4993 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1310,10 +1310,10 @@
     core-js "^3.29.1"
     mitt "^3.0.1"
 
-"@gitlab/eslint-plugin@19.6.1":
-  version "19.6.1"
-  resolved "https://registry.yarnpkg.com/@gitlab/eslint-plugin/-/eslint-plugin-19.6.1.tgz#1e59cb0d83e2f8522945b1b5f01d1fc284b7e729"
-  integrity sha512-VA5eH9U6qr3PH24/hhwNKS4AF3jPB78ZaBmuQipGsn0DlyOqOdg2JnuX7C5tR4yM1D7uK2FcAdrW4AGovEQ7Xw==
+"@gitlab/eslint-plugin@20.0.0":
+  version "20.0.0"
+  resolved "https://registry.yarnpkg.com/@gitlab/eslint-plugin/-/eslint-plugin-20.0.0.tgz#d451169692b3ee51e7e946f6b9cead3de5132a51"
+  integrity sha512-D/nScJCBqR5TMJkg5jpanhTIvrRVsWPohPUUhkHmCrjyXDjjZdZ3hkLZBF66tst0yENFDh6l5mtRVCzCIU5xdA==
   dependencies:
     "@typescript-eslint/eslint-plugin" "^7.14.1"
     eslint-config-airbnb-base "^15.0.0"