This might be useful for the user - what do people think?
A dedicated Activitypub filter in categories view
0 - All posts mixed in topic listing view (current default)
1 - removes activity pubs post from listing view
2 - display only Activitypub post in listing view
Right now (I never knew this till I checked), you can alt-click (Mac) whatever grouping of categories you want listed, but when you want to just take out the non-native ActivityPub stuff, I can't see how to do this.
As I type I'm wondering maybe then perhaps a grouping feature, where a user can make their own filter groups for viewing listings might be the cool solution. However I don't want to overcomplicate anything. There is similar in Discourse and I never use it.
I do think for the UX clear differentiation actions and points need to be available to the user, espcially if blending in ActivityPub content in with native forum content.
For a fast solution this perhaps this could be handled and tucked into the "All Topic" filter button, with at leat two new options:
exclude activitypub posts
show activitypub post only
Maybe allowing that then be the users default until they change it.
Another approach is an exam short-cut, say a Ctrl-Click (or some similar combo) that instead excludes the clicked categories, thus you could filter out "ActivityPUb" (or any category for that matter) using the "All Categories" button.
As well as offering the opposite function using a short key as above, there would probably be a need to give the user a visual UI toggle include/exclude on that menu, so whatever they select they know they are either including or excluding form the list view.
@omega Right now in pages where there is a list of topics (e.g. /recent, /popular, etc.) there's a filter for "Uncategorized", which would essentially exclude everything else.
It's not as clear cut as excluding or only showing local topics, but that sort of achieves what you want. If you only want to see categorized topics, then you needn't select anything at all. By default, uncategorized topics are not shown.
What I think you're advocating for is a button to filter out ActivityPub topics even if they're categorized. That's where I think I might draw the line, because if a topic is categorized, then it is by that action it is considered (at least by the topic mover) to be related to the overall forum topic.