The simple test like:

{
    QString a;
    a.insert(0, QChar(u'A'));
    QVERIFY(a.capacity() >= 3);  // Error!
	
    a.append(QLatin1String("BC"));
    QCOMPARE(a, QLatin1String("ABC"));
}

fails with a.capacity() not being >= 3. This is only visible on Android and other platforms seem to be OK (e.g. Ubuntu/Windows).

The logic of space allocation is not platform specific, so something interesting is happening on Android.