[regression 6.4.2→6.4.3] translator loads wrong translation

Consider the following snippet;

QGuiApplication qapp(argc, argv);
[...]
static const char* languagePacks[] = {
    "tom-mobile",
    "tom-common",
    nullptr
};

for (int i = 0; languagePacks[i]; ++i) {
    auto *translator = new QTranslator(&qapp);
    if (translator->load(QLocale(), languagePacks[i], QLatin1String("_"), QLatin1String(":/i18n")))
        QCoreApplication::installTranslator(translator);
    else
        delete translator;
}

This got deployed with qrc:

• tom-mobile_nl.qm
• tom-common_nl.qm
• tom-common_en.qm

When I run it on the phone the locale.name() prints "en_NL".

The behavior of the above snippet is that on at least one phone I see Dutch (nl) translations appear for the 'mobile' unit.

What I expect is that the common_en translations are loaded and nothing is loaded for the mobile segments.

The expected behavior is what is happening on the released 6.4.2. The weird behavior is observed on the 6.4.3 branch. Specifically:

Fail sha1 (qtcore): aecaf09913771e823575b8b382070a3eaa8aeae6