My rather imprecise suggestion, from: https://trisquel.info/en/issues/13138#comment-80776
Is as follows: Although I'm not using neither GNOME nor Nautilus (as I'm using XFCE with Thunar as file manager), I remember that this seems to be related to the keyboard input method chosen (although I don't have references to prove my point here). Perhaps this can be worked around by opening Nautilus for the first time after login using: XMODIFIERS="" nautilus
