Using Super + Space to switch back and forth between input methods on Wayland (Gnome)

Hello, everyone. I’m using ibus and Mozc for japanese input, and for some reason the default shortcut for switching input methods has a weird behavior, but only on Wayland: Super + Space switches from EN to Mozc as expected, but once in Mozc I cannot switch back to EN with the same key, or any other key that I could find. Gnome Settings says that “Super + Shift + Space” switches to previous input method but the key combination actually does nothing. This works on X11, by the way.

The Mozc shortcut menu is a bit confusing, so I’m not sure where I could configure this. The only change I’ve made to the default config was putting active_on_launch: True inside of the config file in order to drop to hiragana whenever I switch to Mozc. Besides that, it works just fine, but this issue is annoying. What might be the cause/solution?

FWIW, there was a similar report recently for a different input method:

Does it happen in all apps or just GTK ones?

Edit: actually, reading the post you mentioned, I went to test further. The problem happens in Firefox and the gtk4 text editor, but it works fine on Chromium for example, which is a Flatpak. Firefox is just default Firefox. However, it works fine on a Emacs buffer :thinking:

I have the same problem, I can change from English input to Japanese input with the shortcut, but when Japanese input is active the shortcut doesn’t work any more for me to change back to English in most applications. For example, the shortcut doesn’t work on Firefox nor on Emacs (self-compiled, not the Fedora package), but it work on the Files app and on Chromium.

Does anyone have a solution? This is not very easy to google, most results give me solutions to other problems…