Does clicking on
https://addons.mozilla.org/firefox/downloads/file/1067196/gnu_librejs-7.16-an+fx.xpi
(following the small procedure I wrote should amount to that) propose you to
add the latest version of LiberJS?
Is there a way to "trick" the browser saying that it is a newer version of
7.16, yes. Abrowser does not communicate its right version number to
websites. To fight against fingerprinting, I believe. On
https://addons.mozilla.org you can right-click on the buttons "Add to
Firefox", copy the link and paste it in the address bar.
My LibreJS addon was automatically updated. In "about:addons" (that you can
open through Abroser's menu or using Ctrl+Shift+A) you can setup that
automatic update in the "gear" menu (o menu com uma rodinha).
