They have an integration with container tabs, I’ve only used it once but imagine it could be handy: https://support.mozilla.org/en-US/kb/use-multi-account-containers-mozilla-vpn

I don’t have any prior knowledge about it but it looks pretty invasive, I found this interesting article about it:

• https://blog.nem.ec/2020/05/24/ebay-port-scanning/

And this Firefox extension to block sites from scanning local ports:

• https://addons.mozilla.org/en-US/firefox/addon/port-authority/