Please fill in the following items if you don't know the root cause.

Which distribution and version?: Ubuntu 23.04
Which desktop environment and version?: KDE Plasma 5.27.4
Which session type?: Wayland
Which application and version?: GIMP 2.10.34

IBus version?: 1.5.29-rc1

IBus is set according to this instruction.

Issue description: When input method is activated before switching to GTK app, when typing candidate list isn't shown but composing is still active. Also the hot key to switch input method doesn't work and the menu doesn't show when I press the ibus button. The menu appears immediately when I switch to a QT app.

The config is two monitors, one 1920 x 1080 at 100% and another at 1920 x 1080 at 200%.