Excellent service, but this extension needs some work. Right clicking the floating Relay icon should present you with a list of the aliases you already have generated on your account so you can auto-fill them in the E-Mail form field with one click. As it is now, you have to:

Click the floating Relay icon > click on Manage All Aliases > go to the new open tab > sign in > click the copy button next to one of your aliases > go back to the original tab > past the alias email address.

This is a real annoyance that defeats the purpose of the extension entirely. I could just have a link to Firefox Relay on my toolbar to click on every time I need to copy one of those aliases, because that's effectively all this extension is: a floating link.