Control the Commit Message on Merge Pull Request

[Laurent Boivin Pro]

Hi

On Bitbucket Server 5.9, 6.2, 6.6

I cannot figure out how to control the content of the commit message when one merge a Pull Request from Bitbucket web interface.

Goal: prevent the merge if the commit does message does not match a regexp.

Any idea or reference to check?

Thanks in advance

Kind Regards
Laurent