In a board, some forums just don't internet you. For example, I don't care about the italian chit-chat (since I don't speak italian), or the recycle bin (I don't need to read every message from spammers).

Fortunately, Icy Phoenix offers a feature for this situation. You can mark whole forums as "Permanently Read".
That shuts said forum from sending any new pesky "unread" notifications.

It is pretty simple:
 - Click on the forum
 - In the breadcrumbs (small menu at the top-right), click "Permanently Read".
 - Voila!

If you want to do this with a single thread, you should:
(warning, this isn't possible as of right now on the mobile version)

 - Open said thread
 - Look at the breadcrumbs/"quick links" in the top-right of the page (just under forum/faq/search/memberlist/log out)
 - Find a blank check in a green background. If you hover it, it'll say "mark topic as permanent read"
 - Click it!

and voila.

Thanks for adding this here!

BTW, it actually doesn't work in UPI2DB, hahaha... I still see the topics. I guess I'll try to take a look at some point.