Inability to delete branches and edit/delete pull requests on BB Data Center

[Dimitri]

We run a BitBucket Data Center v5.11.1

Couple of weeks ago BB users noticed that they were unable to delete Branches and delete/edit Pull Requests; when clicking on the relevant button nothing happens.

The rest works fine (Branch creation, PR merge...).

I tried as the admin and got the same result.
I looked in the various logs I can see and could not see anything related.
I can't think of anything that has changed recently that would cause this.

I know the BB data center is EOL and we are out of maintenance but would anybody be able to provide some suggestions for things to look at please?

Note that we are planning to migrate to the cloud in the coming months but until then we are stuck with this version.

[Dimitri]

It seems to only be an issue in the web interface as we are able to

- delete branches via "git push origin --delete BRANCHNAME"

- edit/delete PRs via curl/REST API

So it does not look to be related to permission/configuration