Looking for help here. I created a new Firefox profile and wanted to load the Bypass Paywalls Clean Add-on/Extension from the XPI file. So I did what I've always done and got the message displayed above.
Then I went into about:config and changed both xpinstall.whitelist.required and xpinstall.signatures.required to false. Fully exited and restarted the browser but still, no dice.
Anyone know how to fix this?
SOLUTION: go to extensions.blocklist.enabled and turn it to false
"This isn't safe" is very different from "I've arbitrarily decided you shouldn't be able to use that"