Either Lastpass has an axe to grind with Firefox, or the developers are incompetent. This app has nothing but issues since the day I switched from Chrome to Firefox. They are missing several features from Chrome (including copying passwords), the actual Firefox button does not work, and it consistently tells me I have the incorrect password even though it is the correct one. I often have to close Firefox entirely just to re-enter the same password for it to then accept it.

Unfortunately I've already been using Lastpass for years and do not currently wish to change password managers (because of the hassle), if this does not change, I will find another more competent password manager. If the developers are looking to hand their market share to others, the Firefox extension is certainly helping their goals.