UI broken in most of Issuable (Issue, MR, Epic) before utility CSS loaded

Summary

Header UI broken in most of Issuables (Issue, MR, Epic, etc.) before utility CSS loaded.

Steps to reproduce

1. Enable to block assets.gitlab-static.net/assets/application_utilities*.css to simulate a CDN outage to deliver static assets
2. Load https://gitlab.com/gitlab-org/gitlab/-/issues/1

Example Project

Independent from any project.

What is the current bug behavior?

UI in issuable header is broken.

What is the expected correct behavior?

UI in issuable header should be rendered more properly.

Relevant logs and/or screenshots

Full movie: https://www.youtube.com/watch?v=b09wNV1l98k

Output of checks

This bug happens on GitLab.com (14.0-pre).

Ref.

• .detail-page-header-actions class was originally introduced in gitlab-foss!15639 (merged) (as of %10.2)
• !43522 (merged)