This extension is very beautiful and I'm very impressed by its metadata collection. It's a little slow because it takes time to connect to the server (fics aren't saved locally, which poses a security concern, but people might like how it can sync with other devices) and I wish the extension pop up was movable. The extension looks slightly different than what's pictured here (the buttons are shadowed for some reason on ao3 but aren't on ffn??) but tbh unless you're willing to pay for the unlimited version ($4 a month) then you might prefer other extensions.