This reverts merge request !26991

Remove duplicates from issue related merge requests

See merge request gitlab-org/gitlab-ce!27067

Resolve "Improve diff nav header"

See merge request gitlab-org/gitlab-ce!26557

Remove duplicates returned by Issues#related_merge_requests API that
relies on ReferencedMergeRequestsService which returns 2 arrays one of
related MRs and one of related MRs that close the issue(i.e. a subset
of first one). We only need related MRs in this case so just pick the
first array.

- Compare versions header is full width except in the unified diff mode
with no tree sidebar
  - Bar is always full width, but the content within stays centered when
unified and no tree sidebar
- File header is the same height as the "Compare versions header"
- aligns with the design system grid guidelines => 56px
- Diff file headers use a button group, switch icon order to open file
externally being the last option, all buttons will become icon buttons
(icon delivery by @dimitrieh)
- If a file header becomes sticky no rounded corner/double border
problem is visible anymore

Rename environment variable EE to IS_GITLAB_EE

Closes #60080

See merge request gitlab-org/gitlab-ce!27044

Move allow developers to create projects in groups to Core

See merge request gitlab-org/gitlab-ce!25975

Add columns to store project creation settings

Add project creation level column in groups
 and default project creation column in application settings

Remove obsolete line from schema

Update migration with project_creation_level column existence check

Rename migrations to avoid conflicts

Update migration methods

Update migration method

Serverless backend now uses `gitlabktl` tool

Closes #56252 and #58058

See merge request gitlab-org/gitlab-ce!26926

Upgrade Gitaly to v1.33.0

See merge request gitlab-org/gitlab-ce!27065

Add color util classes for backgrounds and text

See merge request gitlab-org/gitlab-ce!26898

Update stylelint error formatter@1.0.2

See merge request gitlab-org/gitlab-ce!26860

Merge branch 'ce-9262-move-project-search-bar-into-modal-dialog-on-operations-dashboard-page' into 'master'

CE backport: Add reusable project_selector component

See merge request gitlab-org/gitlab-ce!25036

Add checkbox to choose to create new list when creating new label

See merge request gitlab-org/gitlab-ce!25716

Backporting EE changes to CE

See merge request gitlab-org/gitlab-ce!26871

Do not inherit when calling const_get

See merge request gitlab-org/gitlab-ce!26985

Extract EE specific files/lines for quick actions tests

See merge request gitlab-org/gitlab-ce!26872

Revert "Merge branch 'if-57131-external_auth_to_ce' into 'master'"

See merge request gitlab-org/gitlab-ce!27051

Revert "Merge branch 'require-all-templates-to-include-default-stages' into 'master'"

See merge request gitlab-org/gitlab-ce!27053

Resolve "Shortcut to create merge request from Web IDE"

Closes #57482

See merge request gitlab-org/gitlab-ce!26792

[CE] Add saml provider to user build service (Backport EE 10456)

See merge request gitlab-org/gitlab-ce!26903

Resolve "Support creating new file from URL in the Web IDE"

Closes #57668

See merge request gitlab-org/gitlab-ce!26622

Add ee_else_ce to Jest config

See merge request gitlab-org/gitlab-ce!27040

Enable FindCommit caching for project and commits pages

See merge request gitlab-org/gitlab-ce!27048

This reverts merge request !26954

Removes the undescriptive CI Charts header

Closes #59905

See merge request gitlab-org/gitlab-ce!26869

Additional changes include removal of translation records

Added changelog

This reverts merge request !26823

Remove spaces from  variable name in CI variable QA test

Closes gitlab-org/quality/nightly#91

See merge request gitlab-org/gitlab-ce!27042

This reduces a handful of duplicate FindCommit calls while viewing the
projects and commits pages.

CE port of Move "Authorize project access with external service" to Core

See merge request gitlab-org/gitlab-ce!26823

Move Contribution Analytics related spec in spec/features/groups/group_page_with_external_authorization_service_spec to EE

Add a length limit of 128 char to the user name field

See merge request gitlab-org/gitlab-ce!26146

Redirect Kubernetes installation to the charts docs

Closes #58870

See merge request gitlab-org/gitlab-ce!26159

Docs for combined ref pipelines

Closes #59495 and gitlab-ee#7380

See merge request gitlab-org/gitlab-ce!26762