Port EE System Header And Footer feature to CE
What does this MR do?
Moves "System message for every page" to Gitlab CE
related EE MR: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/9556
What are the relevant issue numbers?
Does this MR meet the acceptance criteria?
- Changelog entry added, if necessary
- Documentation created/updated via this MR
- Documentation reviewed by technical writer or follow-up review issue created
- Tests added for this feature/bug
- Tested in all supported browsers
- Conforms to the code review guidelines
- Conforms to the merge request performance guidelines
- Conforms to the style guides
- Conforms to the database guides
- Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.
- Security reports checked/validated by reviewer
Closes #55057 (closed)