Issue Summary

When a PR is automatically closed because another PR was merged that contains the source branch’s ref, the UI shows a refresh popup on windows showing that now-defunct PR.

{"type":"error","error":{"message":"Can only update an open pull request."}}

Steps to Reproduce

1. Create a repository with a single commit on the main branch
2. Create a second branch, oldmain
3. Create a new branch, `soon-to-be-defunct`, add a commit of any kind, push and open a pull request to the main branch
   • Leave the pull request window open
4. Create a new branch based off soon-to-be-defunct named mergeme, add another commit on top of it, push, and open a PR from mergeme to main
5. Merge the mergemeto main PR
6. In the soon-to-be-defunct to main PR window, disregard the refresh popup and attempt to retarget the PR to oldmain.

Expected Results

more targeted error popup

Actual Results

• The PR update PUT returns a 400
• The UI shows “Something went wrong”

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available