Call to undefined function forum_access_entity_access_by_tid()

Examining the code, it seems to be a simple matter of a missing moduleHandler->loadInclude() in that hook. Maybe, though, this is a good opportunity to start converting Drupal 7-style includes to a modern Drupal serviche architecture.

I think this is now good to go. Maybe a bit ambitious for a simple bug fix, let me know what you think.

I also created MR 16 that simply adds the missing load include. Feel free to use whichever you like.