Tricky on Kobo, the only toolkit available is an old Qt5 version that handles input in a non-standard way.
(i.e., even native Qt apps won't work OOB).
Which is why so far stuff relying on Qt has been building its own Qt version and cooking up its own QPA.
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And that's for native C++/Qt. Python adds another layer of fun to the mix, which I won't even bother going into because it's irrelevant given the native issues

.