You can either install it unsigned with Firefox Developer Edition and it will be permanent. Or you can sign it yourself (you don’t need to publish it on AMO): https://extensionworkshop.com/documentation/publish/signing-and-distribution-overview/ and it will work on regular Firefox.
Great response!
If he replies with something like « I need you to come in » you should follow up with « I’m sure you do, good luck dude. »
Never break it, that’s hilarious.