As written, this button will automatically operate on the entire containing folder when one or more files inside it are selected. (I assume this is a function of the "sourcepath$" operator, though I tried replacing it with "filepath" and ther result was the same.) Is there a way to modify it to operate only on the selected file(s) and/or folder(s)?
Opus will run it once for each file, which seems to work with Mp3Tag. Other methods can work better with other programs, depending on how their command-lines work.
That does work, thanks, but now the button won't work on any selected folder(s). If the selection contains one or more folders, I would still like the button to operate on all the tracks inside. And if the selection contains both files and folders, I would like it to operate on the selected files plus the selected folders' contents. This is how MP3Tag works when executed from the context menu. But at the moment, if the selection contains both file(s) and folder(s), the button only works on the files.