one thing that boggles me about the firefox dev team is their continuing refusal to add a "disable ctrl-Q" setting. it's right next to ctrl-W and in my firefox using days i accidentally hit it a ton of times.
Chrome used to "honor" the backspace key means navigate backwards so much that if you hit tab (changed focus) while typing a textbox then hit backspace it would nav back and lose all your text. Made me cry so many times.
You might like one of the add-ons that disable Ctrl-Q.
There used to be one such Firefox addon that even made it into the Debian (Wheezy/Jessie) repositories. Unfortunately it was written for the old plugin system and never updated and is now designated as blocking the new Firefox multiprocessing, so I already started looking into Firefox addon programming just to replace it. Somehow I never thought about looking for newer alternatives in the official addon store, where several modern ones seem to exist already, so I'd like to thank you a lot for your suggestion.