This is probably related to QTBUG-42277.

The dropped() signal from DropArea carries a "drop" parameter which contains an "urls" member, of type urllist. While this member can be saved and stored into another variable while the signal handler is executing, it seems that any copy of this variable get reset once the signal handler terminates.

Please try the attached test case, and drop some image files from another application. One would expect to see the same list of URLs being printed twice, but the second console.log() is not printing anything.

This but is made worse by the fact that its natural workaround (copying the url list one member at a time) is unbelievably slow (it takes about half a second to save each element!), which is probably another bug per se.