Multiple login issue IS addressed in 4.0.2 and it works fine. If you updated from 3.x, then reinstall the old version from the version history, export the settings before updating, and then re-import them after updating to 4.0.2.

In using the extension, I didn't really use it to do anything fancy - so everything seems to work the way it did. Only difference I can see is that it takes one more click to open up all the mail accounts at once; but I used to do that by accident all the time, so I don't know if this is something that I am too unhappy about.

Kudos to the developer for taking the time and effort to port it to the new standard. Many developers in the past have abandoned development on their extensions when something like this happened, and I am just grateful that this one is going to survive another generation of firefox.

That said, I DO wish more of a warning was given so that people did not think all their mail account setting went up in smoke, but I don't know what the developer could have done.