I have no idea (virtually zero experience with Linux), sorry. Since a standard browser API is used, in theory it should as good on Linux as on Windows or macOS . How does it look? You drop a file into the viewer and nothing happens?
Sorry about the late reply. Yeah, the mouse over with the dragged item does not even change to show it is droppable there. It does however, drop outside the viewer in the same webpage, but then that only makes it so that the viewer's webpage goes to the code contained in the file (a la, using a browser to open that file's code/script). Very weird.