This is a very simple example for me. You can download this case, start index.html as a service, and then input Chinese to see the same effect as GIF image
Thanks for providing a demo case. I didn’t manage to reproduce any infinite loop with that though. I did notice that text composition broke, and the editor would create overly deep DOM structures, so maybe I was seeing a related bug. This patch addresses that. Could you take a look to see if it solves your problem?