4.1.4 fixed the Hotmail issue for me as far as I can determine now, Thanks!
Works fine with Gmail and Yahoo as well on my FF ESR 52.3.
Dang Mozilla developers keep breaking extensions every 6 weeks and I'll have none of that. If you have problems with your extensions (including this one) roll back to an ESR version such as 52 and don't let it auto update until long past the ESR expiration date and even then be careful, Mozilla probably has broken everything very badly by then. If possible use an alternate Mozilla based browser that uses the older base, if your extensions work on it. I had to give up SeaMonkey finally because of some update on it and none of my extensions, and half the things I expected on it worked! (This was a couple years ago now.)
Don't know why they don't make sure ALL extensions work from just one version to the next when they get another version (Chrome seems to work fine no matter the version, and FF has become more and more like Chrome since the stupid rapid update process EXCEPT for this.) At the very least Mozilla could re-write ALL the extensions to work with the new version, instead of depending on the developers of the extensions to do it, and not change versions until they do, say every three to four years.