Thank you for your answers!
For number 1, I’d just like the ‘find in file’ window to behave like it does when using a simple search (stay open until I close it). I do many consecutive searches into files (for example to count occurrences of a series of words), and I have to reopen the search window every time. It’s quite annoying, it would be useful for me to have an option in settings to disable auto-close.
For number 2, the workaround you suggest (bottom-up editing) works perfectly, I posted this request just for a possible future implementation (actual behaviour is useless because results become invalid after an edit). It’s just a matter of actual behaviour vs expected behaviour.