Okay, maybe it isn’t a javascript issue then. If you’re using safari, can you open the web developer tools and go to the network tab after you load the PTE interface? (clear all the network calls so it will be easy to see the next call)
After you select the thumbnail to crop and the area, press the crop button, there should be a call made to the resize-images function (which is a function that changed in 2.4.2), see what the response from the server was. I’m guessing that there was a problem with the nonce. If that’s the case can you paste the URL of the call here and output?