Sounds good.
This person here: https://github.com/aristath/kirki/issues/2177
had the same issue.
It has to do with Kirki downloading fonts to the server, which is now required for Xstore, and perhaps not adding the www. after https:// which maybe causes the CORS error. I don’t know much about CORS issues, and I need www. for my Cloudflare CDN, but that’s my theory.