This is fixed on latest master/persona/vanilla.
I fixed the issue by adjusting notifications_list.tpl:
How to add the Solved/Unsolved badge to NodeBB topics?
Hello @H7 -- you'll want to use the Q&A plugin: https://github.com/NodeBB/nodebb-plugin-question-and-answer
You can find it in the Plugins menu, or if not, then you can likely install it via npm.
@julian Thank you!