Allow opening files from file manager
Please add just a simple button to Gnome Books to allow the direct opening of epub files.
This way there's no need to copy the epub files to the documents folder; no need to add any new folders to the app, just click "Open" which pops up a GtkFileChooserDialog, and you start reading the book, without worrying about the remembered position in the text or status within the library. It could be a button, it could be a menu, it could be a shortcut combo - you decide.
That would be a very useful thing to have!