Thanks Milan! Installing qml6-module-qt-labs-settings didn't resolve
the reported error, though, but helped me get webcamoid running nonetheless.

To resolve `module "QtQuick.Controls" plugin "qtquickcontrols2plugin"
not found` warning, qml6-module-qtquick-controls needs to be installed.
But wait! There's more!

Next warning: module "QtQuick.Layouts" is not installed
Resolution: install qml6-module-qtquick-layouts

Next warnings: Now we get `module "Qt.labs.settings" is not installed`
as well as `module "QtCore" is not installed` which is resolved by
installing qml6-module-qt-labs-settings plus qml6-module-qtcore. We're
not done yet, though!

Next warning: module "Qt.labs.platform" is not installed
Resolution: install qml6-module-qt-labs-platform

Now, webcamoid starts, but even more dependencies may be required which
I already had installed. Fortunately, the missing module names reported
mapped to a package name consistently. Try apt install
qml6-module-<TAB><TAB> to see all available.

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