Why do you do S-C-x in Firefox? Are you using some add-on that gives
you Emacs bindings there, or?
no you misunderstood me, I want to avoid to learn any new emacs
keybindings that have a very different meaning in other applications.
e.g C-w closes a tab in FF, thats why I want to restrict me to always use C-x for cutting, otherwise I have restore FF-Windows 10 times per day.
Actually emacs keybindings are mentioned in the FF docs - something about activating them in Gnome would also activate them in FF. But I couldn't figure out how.