Comment 45 for bug 1357895

Believe me, I understand. In fact I am a multilingual user myself and I was very used to that exact same keybinding of using both shifts together, I just used both pinkies all the time, I am just starting to get used to Alt+space. I tried to understand why gnome took the decision of overriding the xkb configuration, and the reason (as far as I could understand) is mostly that xkb is not the only input method out there (see pinyin on ibus for example), so to actually support an ever bigger multilingual user base they had to compromise some stuff.

I am very open to hearing ways in which this could be brought back but we can't implement stuff that will make harder for us to get better ibus support in the future, I couldn't come up with a better solution for this than the one I implemented.