<!--IssueSummary start--> <details> <summary> Everyone can contribute. [Help move this issue forward](https://handbook.gitlab.com/handbook/marketing/developer-relations/contributor-success/community-contributors-workflows/#contributor-links) while earning points, leveling up and collecting rewards. </summary> - [Close this issue](https://contributors.gitlab.com/manage-issue?action=close&projectId=278964&issueIid=336044) </details> <!--IssueSummary end--> ### Context We have supported using the timebox values as wildcard in the param `milestone_title` when filtering issues by milestone. This interface is problematic in that 1) when the title of a milestone exactly matches one of the timebox values, the milestone may get omitted as filtering criterion. 2) it doesn't match the conventions used for other objects like iteration. `milestone_id` will be added to support specifying milestone timebox wildcard values in https://gitlab.com/gitlab-org/gitlab/-/issues/335939 and then we can safely remove the current usage of timebox values in `milestone_title`.