It’s a little counter intuitive to configure, but the key is to match the “slug” for an existing tab precisely. (i.e. for Forums, the slug is “forum”) If you don’t put the slug in exactly, it won’t use that tab as the default. Works perfectly.
There is/was a plugin called “BP Default Group Tab” which worked perfectly. It’s a premium plugin from BuddyDev that’s still offered. That said, it seems not to be working anymore, which is such a shame. Now I’m trying to make Forum the default landing page for my groups, and have been struggling for days… I can find old code from 12 years back, but nothing that seems relevant to the newer Buddypress code.
