Before being able to hit enter to view a book, the user would first have to figure out how to add a book. And there is no standard keyboard shortcut for that. I'm afraid I find the argument that users that first figure out how to click the Add Book button, then cannot figure out how to click the View button, unconvincing.
Indeed, I find the entire line of argument that users cannot figure out the most basic of things unconvincing. Users of that stripe are highly unlikely to have figured out how to download and install calibre in the first place. And even if they did, they are likely to get lost as soon as they need to do anything beyong viewing a book.
What I am sympathetic to is an argument around conventions. If it is conventional to so something, it can be annoying if your convention does not work in a new context. It does not, however, mean you cannot figure out how to do the action. So
https://github.com/kovidgoyal/calibr...37d56325b8d686