Rated 1 out of 5 stars
Tried on only 1 site, I only installed for that, and it's not working at all.
I only see the brown blackground for 3-4 seconds, and the page keeps trying 2-3 times in a second, even if the login options filled, but thats all, doesnt login.
If the Firefox Password Manager did manage to save your password correctly and a special login bookmark is indeed created and used, should be able to auto-login. Perhaps the latest version 0.4.4 at https://addons.mozilla.org/firefox/addon/the-idle-login/versions will work.
As you have not used the add-on for other login sites and auto-login to them successfully, so can't really pinpoint the exact reason and find solution for it.