Bitbucket Server Protect Unmerged Hook
for Bitbucket Server 5.0.0 - 8.4.1, Bitbucket Data Center 5.0.0 - 8.4.1 and more
Rejects pushes that delete branches involved in active (not merged/declined) pull requests
Configure your hooks
Enable this hook through your repository settings.
On push the hook will check and reject the push
If you try to delete an unmerged branch the hook will check for this and reject the push.
Once merged or declined deletes are allowed again
When the target branch is merged or declined it will be again possible to delete it.