We have updated our app from qt 5.15.4 to qt 5.15.5.
Since then our errors on clients explodes with the following message:

• • • *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
      pid: 0, tid: 0 >>> myapp <<<

backtrace:
#00 pc 00000000000830f0 /apex/com.android.runtime/lib64/bionic/libc.so (abort+160)
#00 pc 000000000009ce88 /data/app/myapp-BtXlmB-Cl3mgfugHwGzCQw==/lib/arm64/libc++_shared.so
#00 pc 00000000000b028c /data/app/myapp-BtXlmB-Cl3mgfugHwGzCQw==/lib/arm64/libc++shared.so (_cxa_pure_virtual+16)
#00 pc 00000000003bad5c /data/app/myapp-BtXlmB-Cl3mgfugHwGzCQw==/lib/arm64/libQt5Quick_arm64-v8a.so (QAccessibleQuickItem::text(QAccessible::Text) const+268)

Unfortunately, we do not know by which component or function of ours QAccessibleQuickItem is used. Thus, we can not narrow down the cause. However, since in comparison to our old version only minor things were changed except for the qt upgrade, we assume an bug in qt.