I mostly don't use mouse, and doing everything from keyboard while working. But the most annoying thing is that while making something awesome in code editor or reading something good in firefox you can suddenly press Ctrl+Q (which exits from browser immidiatly without warnings) or Alt+F4 when you want to press Alt+F3. Everytime I loose time because of that hotkeys.
So, today finally I changed my keyboard layout after closing code editor with unsaved code and important sorted data.
In Ubuntu just open System Settings and then Keyboard:
Then edit current key combination to make it hard and unique (click once on it to change):
Now go to Custom Shortcuts and add new keys with /bin/false command which will do nothing:
After adding combinations here these keys will do nothing and you will never have such problem again. Just remember changed hotkey to not search later why they are not working :D