<!--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=31116) </details> <!--IssueSummary end--> ### Summary Reopen merge request should trigger pipelines for merge request. ### Steps to reproduce 1. Configure a pipeline for merge requests (https://docs.gitlab.com/ce/ci/merge_request_pipelines/index.html) 2. Open a merge request from a branch 3. The pipeline for merge request is triggered 4. Close the merge request 5. Push some commit to the branch 6. Reopen the merge request ### What is the current *bug* behavior? When reopen merge request, the pipeline is not trigged, even there are new commits for the branch. And users can not trigger the pipeline manually, either. ### What is the expected *correct* behavior? When reopen merge request, the pipeline for merge request should be trigged (as if the merge request is newly created). If no commits are updated, the pipeline could not be triggered as an optimization. A rebuild button could also help. gitlab-ee#311, gitlab-ce#65940 Creating a new merge request is an acceptable workaround since we have to retype everything (description, labels, milestones, assignee, etc). ### Output of checks This bug happens both on GitLab.com and self-managed gitlab-ce installation.