accessibility: QComboBox editable unable to navigate by left/right arrow keys

hello.

i was exploring qt widgets accessibility state with properties enabled and discovered that:

if using QComboBox widget with setEditable(true) for screenreaders combobox is not fully editable.

actual result:

when navigating through control with left/right arrow keys, screenreader should announce letter under cursor and backspace should announce deleted letter.

actual result:

after setting editable property to true, combobox becomes editable, i can enter a value in it but for screenreader it is not an editable combobox, nothing is beeing read on left/right arrow key press and i don't know what i am deleting on backspace press.

tested on windows 10, NVDA 2019.3, macos 10.15.4 with voice over, ubuntu 20.04 with latest orca.

in all this operating systems issue presents.