(Graphical) IDE's are great for development, but they're slow to start and heavy to run. Sometimes you just want to take a quick look at an xml or dockerfile and you don't want to spin up the whole IDE for that.
I've recently rediscovered notepad++ for that (on windows), what's your prefered easy-acces-tekst-editor?
I had the problem a week or so ago. I deleted my settings file and it started working again.