If any crash dumps were generated, please send them to us so we can investigate:
If you go back to 12.9 does the problem go away? I can't think of any changes in 12.9.1 which would start to cause that problem.
It's possible the crash is not in Opus and is a shell extension something else has installed going wrong, but we can usually use the crash dumps to see if that's the case.
If there are no crash dumps, this guide has other suggestions on tracking down the cause of this type of crash: