Switching keyboard layout would not do anything in some apps, notably Steam, Chatterino, Viber.
These apps act as if there is only one layout and it’s always the first one on the list.
Telegram, Konsole, Dolphin, LibreOffice Writer, Kate all operate just as I would expect.
Chrome and Discord work, but have this weird behaviour where pressing backspace will reset the layout back to the first one.
I tried making IME style input working through something called “fcitx” and “mozc” in the past. Not inputting any Japanese for now. I think that might have interfered.
Please suggest packages and settings to check in order to sort this out.