I am yet another person whose Lastpass addon for Firefox stopped working on May 4, 2019. It has been removed from add-ons. When I try "+ Add To Firefox" again, I get the message "Download failed, check your connection".
Also, if I download lastpass_password_manager-4.27.2.10-fx.xpi and try to manually install it, Firefox says that the xpi file is "corrupt".
I am on my way to the lastpass site to also report this to them.
UPDATE: I found a fix. See this post within the LastPass forum! ...
