After I add any stories to an existing shelf, the browser hangs, and I need to close/reopen the tab. This happens on both Chrome and Edge on MacOS.
Sorry about this. I’ve just fixed a bug that was causing it to hang when adding to shelves (in my case for only a couple of seconds but I think it will get worse with more texts). I’m not completely sure that this was the same issue you were having so please refresh your Readlang browser tab and let me know if it’s still happening for you.