how can a user run a protected manual job?

there are several jobs in the protected branch. the last job is manual, but regular users cannot run it. how can an ordinary user run a manual job in a protected branch?

in the picture, an ordinary user does not have a play button

Solution

Only users who can push or merge to a protected branch are allowed to run manual jobs for a pipeline on a protected branch.

See footnote 5: https://docs.gitlab.com/ee/user/permissions.html

[Run CI/CD pipeline for a protected branch] If the user is allowed to merge or push to the protected branch.

Thus, the only way to allow a user to run this job on a protected branch would be to give them permission to either push or merge to the protected branch.