[wildophanim]

I had been trying to open multiple files from a file folder in the reader app without adding all the files to the calibre library, but only one file would open of the batch I selected. Then I discovered this when I used right click rather than hitting enter.

To open multiples, select your files from the folder up until you right click and can still see the 'open' option in the menu that opens. If that option disappears, you have selected one too many and calibre will only open one to view. I think the default number is 15.

I found this out of desperation to open a batch of epubs all at once without adding them to calibre library. Microsoft Edge used to be my go to method, but this works, even if I'm limited to 15 or less.

Hope this helps someone.