When adding to a Playlist one must press “Complete”. If successful there will be a message "Added to Playlist. If adding the media was not successful sometimes there is a message “failed to add” and sometimes there is nothing. There should be some sort of consistent error message.
As an aside, “Complete” while not incorrect isn’t really appropriate in American English. The message should be something like " “Finished Editing” or “Add Selected Media” or “Editing Completed”.
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