To reproduce : copy a file from windows file explorer and paste it into a widget that extracts the URL path with the following commands:

QClipboard *clipboard = QGuiApplication::clipboard();
const QMimeData *mime = clipboard->mimeData();
QString path = mime->urls().first().path()

the result is something like this :

/C:/folder/file.txt

Instead of the following expected result :

C:/folder/file.txt