Firefox 57 introduced a new extension API that broke most of the extensions I had been using, including It’s All Text, Dorando Keyconfig, and Tab Mix Plus. So I installed Pale Moon, a fork of an older Firefox that works with those extensions. But the current LastPass extension only works with the new (57+) Firefox.
A few months ago, I was able to find a copy of LastPass 3.3.4 on the Firefox web site; this is the last version that works with Pale Moon. Then today I tried to install Pale Moon on a second machine and discovered that LastPass 3.3.4 had been removed from the Firefox site, and I couldn’t find it anywhere else.
The solution was to recreate the xpi file for the extension using the existing installation. Here’s how to do that:
Pale Moon extensions are stored in
~/.moonchild productions/pale moon/xxxxxxxx.default/extensions/,
xxxxxxxx will be a seemingly random sequence of letters and digits.
In that directory, the LastPass extension is stored in the subdirectory
email@example.com. Move into that directory and then execute this command:
zip -r /tmp/lastpass.xpi .
Copy the resulting xpi file to
/tmp on the second machine. In Pale Moon
on that machine, enter this URL in the address bar:
The extension should install and be available upon restart of Pale Moon.