Sometimes, the build progress bar does not take up the full width it is allocated, resulting in screenshots like https://github.com/jenkinsci/jenkins/pull/6562#issuecomment-1133440939 or https://gitter.im/jenkinsci/ux-sig?at=62912c2cef00bd1dc6011778

janfaracik in https://gitter.im/jenkinsci/ux-sig?at=629157844e38f759e28ff91c proposes an issue with Bootstrap.

Steps to reproduce

1. Install Jenkins 2.350
2. Install Warnings NG plugin 9.12.0 and its dependency bootstrap5-api 5.1.3-7
3. Create a freestyle job
4. Add a build step that sleeps for 20 seconds (e.g. shell sleep 20 )
5. Add a post-build step that "Record compiler warnings and static analysis results", leave all options default
6. Save
7. Trigger 2 or more builds
8. Wait a while

Expected result

Sane progress bar

Actual result

See attached