Non-Latin characters don't work on the On-Screen Keyboard.

Cyrillic symbols and most non-latin language specific symbols like "ó" and others type "1". In desktop mode, when english layout is chosen in KDE, cyrillic OSK prints nothing, when changing layout to russian, latin OSK prints cyrillic, while cyrillic OSK prints nothing again. There is a similar issue for chinese language #45 . I tried installing IBus, did not help. Also, russian layout and others with non standard symbols like italian for example, do not have a message asking to join the system preview channel, like chinese and japanese do.