[Ripplinger]

That's a broken substrate and was just coincidence that it appeared with the new firmware update. It results from some damage, like something pressing against the screen, or flexing the reader a bit can crack it as well. There's no fix for it unfortunately other than getting a new reader and being more careful and probably use a good cover with it.

You'll need to edit your post and upload the image to MR so it won't be deleted when a mod comes by and sees the image (the size is larger than allowed for inline images).