[mh-]

Since one of the parent comments mentioned AJAX, I'll add that you'll also be prevented from eval'ing that payload.

[oefrha]

Yes, I should have been more clear: CSP doesn’t allow you to download an external script and execute it, which requires unsafe-eval.

[TeMPOraL]

Sounds like your exception will need to become a language interpreter itself.

[TOMDM]

Does manifest v3 support wasm?

Time to package a JavaScript interpreter into wasm and run it within the extension.