FireFox: Sandbox / Failed to include script files

[thetrung]

I have included <script src="./index.js"></script> into of index.html

but in sandbox page, it still show error :

<script> source URI is malformed: “https://www.fxhash.xyz/sandbox/index.js”

** UPDATE:
saw this a lot in discord too, and seem like Chrome will run just fine for this. But is there anyway to work around for FF ?
Also, I think we need to take note on README to warn ppl.