Donoreo This is not a bad idea really. However, it would definitely be annoying for the tags you don't ever visit. There would always be unread posts showing. I know Flarum is highly extensible, but I'm noticing a lot of oddities that should just be standard in forum software, lacking in Flarum. I might spin a copy up and play around to see if I can find anything that someone here might be missing on the extension side. Perhaps if the extension coding process isn't insane, I might even try my hand at making one for something requested here.
Edit: Ooo looks like I can spin up a docker on Unraid of Flarum. Weeeeee