Fix CORS restrictions on Firefox

[kevmo314]

For some reason, Firefox seems to be very unhappy with the cross-origin requests out of the background script from the extension. I've posted about this here: https://discourse.mozilla.org/t/bypassing-cors-restrictions-on-background-scripts/113839/2

But I have no idea how to fix this after a few hours of trying different approaches. I don't think we can reliably do the fetch in the content script either.

This appears to be the last remaining issue for Firefox support.

[ajtadeo]

hello, I am working on a similar project that uses a content script to modify images on a web page. have you found a solution to these CORS errors? i've also not found a way to resolve this problem.