[DaringSteel]

I'm on a Mac, using Calibre's built-in viewer. When I select a book in the library and click the "View" button (the one with the description "Read book"), instead of opening the book for me to read, the "Adding books" window pops up, quickly followed by a helpful alert that Calibre has found a possible duplicate of this book which I am clearly trying to add to my library.

(I understand that people have different preferences for interface format. If that's what this is, it would not be even close to the weirdest norm I've seen thousands of people accept without question. But it's impacting my reading experience, and other people have posted things that make me think "View" is supposed to open the book in readable format.)

How can I set up Calibre such that, when I select a book in the library and click "View," it opens in a form that I can read it?

Details:
- This also happens when I hit the "v" key shortcut, or right-click>view, or select "View" from the drop-down menu next to the "View" button, or double-click on the book - all the ways I know of to invoke the default "View" option from inside Calibre itself.
- To actually read the book, I have to go into the "View" menu and pick "View with calibre E-book viewer," which works as advertised.
- I don't have a precise number for how long, but this has been present since I first tried Calibre some years ago (which actually ended in me giving up on it, because I couldn't figure out how to read anything except the quick-start guide).
- Basically all the things I have in my Calibre library are CBZ files (not because I only read comics, but because PDF/EPUB/etc. files open in Preview or Books by default). The default quick-start guide EPUB opens normally with the "View" button.
- The window that pops up when I open a CBZ file from Calibre is the same one that pops up when I open the file from the Finder window.