Thanks I managed to reproduce this problem.
I don’t think it has anything to do with latex and titile.
If you have two or three notes open and you shrink the obsidian window, at some point the UI will break and you’ll start loosing UI elements.
Idk if the in-page search function will be augmented soon enough, but just in case it wasn’t mentioned (maybe under some keyword I couldn’t think up) I can’t find the “close” button here for CTRL+F when I’m working with multiple views :
But when it is just a single view, the close button is there: