Loading QtQuick.TreeView 2.15 plugin fails

Hey, I am using Qt 5.15.8 and I built the QtQuick TreeView from this sources https://code.qt.io/cgit/qt-extensions/qttreeview.git/tree, following the build guide in the README.md. The building works fine and sudo make install also succeeds. I end up with a folder in "/usr/lib/qt/qml/QtQuick/TreeView" which contains: libqquicktreeviewplugin.so  plugins.qmltypes  qmldir  qt5/

Running ldd on the library shows that the Qt5 libraries are linked to it, as expected.

Now creating a simple templated through Qt Creator (Also using Qt5), and using "import QtQuick.TreeView 2.15" in my main.qml file leads to a runtime error, saying: {{qrc:/main.qml:3:1:
plugin cannot be loaded for module "QtQuick.TreeView": Failed to
extract plugin meta data from
'/usr/lib/qt/qml/QtQuick/TreeView/libqquicktreeviewplugin.so'}}

Does someone have an idea why this might happen?
Thanks in advance