I am running Xubuntu 20.04 on amd64.
When I installed a Korean keyboard layout ("input method") through IBus, a small window appeared on my screen.
xwininfo I found that this window is titled "ibus-ui-gtk3".
The window has options relating to the Korean input method (e.g. a button to toggle between hangul and hanja). However, the window never goes away, even when I switch to a different input method (e.g. English).
How do I make this window go away, or at least only show up when using the Korean input method?