Is it possible to return Access-Control-Allow-Origin: * in response to preflight request instead of existing Origin header?

[vollossy]

I'm developing figma plugin and figma uploads plugins html from local filesystem, in this case, all requests will have 'Origin: null' header and thus Access-Control-Allow-Origin will have null, which, in turn, leads to CORS error in browser. I've checked preflight_handler.py source and did not found any way to change usage of existing Origin header value to externally defined one(*). Am I missing something?