I’m not quite following.
If you go to the community and sort by new you’ll see new posts? That seems to be what you’re asking.
Also see the “scaled” option for your subscribed feed. This makes low activity communities show up higher in the list to try to stop them being drowned out by high-activity communities.







Oh so when you said:
You weren’t asking for a way to see posts for a particular subscribed community, you wanted a list of communities with the number of new posts in each?
I’m not aware of a way to do that, no. But I wonder if the communities list page might help you find them? If you go to the communities page and sort by Scaled, like this:
https://discuss.online/communities?listingType=Local&sort=Scaled&page=1
Then small communities with recent activity should show at the top?