Android: unresponsive app after showing keyboard, suspend, resume

QML-based Android app becomes totally unresponsive after:

• Focus on text field
• (Android virtual keyboard is shown)
• Lock screen (by pressing power button)
• (Android does all sleep-preparation stuff, few seconds of waiting should be enough)
• Unlock it back

It shows black rectangle instead of app, Android input cursor and keyboard, but there is no way to either close keyboard or interact with app itself. Back button doesn't work, clicking on app doesn't do anything. After some time android issues ANR with Input dispatching timeout reasone(line 1063 in logcat).

It seems like it can be related to https://bugreports.qt.io/browse/QTBUG-40955 , but I'm not sure.

I didn't try the same app with Qt 5.10, but initial app where I found this issue worked fine (i.e. unlocked properly) when was built with 5.10 and showed the same symptoms with Qt 5.12.

In attachment:

• android-freeze-test.tar.gz - tar.gz with sample project. It is mostly a QtQuick Window template from Qt Creator, that uses Android stuff from Qt itself (i.e. proper AndroidManifest.xml and no custom Java parts)
• android-build-debug.apk - apk built from that project using latest SDK/NDK provided by Google and Qt 5.12.0
• logcat - output of adb logcat
• build_log - output of build process from Qt Creator 4.8.0