I can post a video if needed but the editor is basically unusable for me after the update. It scrolls all the way back to the top of the file and all over the place every time a line is added or removed.
I’m running Nova 11.5 (Build 550229) with macOS 14.0 Sonoma (23A344) on an M2 MacBook Pro.
First, in Nova, go to Settings… then in the General tab, uncheck Automatically keep Nova up to date. Then you can get Nova 11.4 from Panic File Muesum and you should be able to replace it.