I am using the latest 13.21 x64 build 9416. It seems that if I select a directory with over ~200 files (mine has 540) and right click to bring up the context menu opus just shuts down and restarts. I am right clicking to bring up the mp3tag program. This works fine outside of OPUS in say the windows explorer so it isn't the MP3tag program or windows. The log due to the restart is clean and there is nothing to show. you should be able to replicate this fairly easy with what I have given you. I tried 238 and it failed I didn't go lower to see where the break point is since I did do like 200 and it worked fine I believe. Lost count.
That is probably caused by a shell extension something else has installed, and not Opus itself.
See here for how to track down the cause:
I've tried with thousands of files selected and there's no issue on Opus's side of things. It will either be a shell extension going wrong or a bug in Opus triggered by a particular file that happens to be in the mix. Once the cause is isolated, we can advise further.