With Bitbucket 5.15 in the pull request view the commit message of the selected commit was displayed on top. With Bitbucket 7 the message is only available as a tooltip. Could you please make the commit message visible again? If you feel many users do not care about commit messages: Maybe the display of the commit message could be configured to let the users decide.

Example screenshots:
Bitbucket 5.16:

Bitbucket 7.4: