St widgets do not follow per monitor scale factor under wayland
With two monitors, one is 4K and another is 1080P, so I set scale 200% to 4K and 100% to 1080P in Settings->Display->Scale. While all GTK apps like Terminal follow this settings, shell widget seems not follow it, a easier way to open two terminals and put them into different monitors, then type with iBus, you'll see different size of iBus candidate panel, the one on 100% scaled monitor is too large and hard to use, it seems drawing in 200% scale.
Here are screenshots, two terminals have the same font size, but candidate panel is too big on one.
Edited by Alynx Zhou