maybe someone might be interested as described here::: Disable install-global-extension so the only option to install .XPI is to copy them to extension folder and when lunch Firefox it will detect and install them... but extension is a subfolder of Profile which is something like that XXXXX.default ( where xxx is random) so so far so good.... so here is an silent install doesn't matter what is the name of profile folder: @ECHO OFF setlocal EnableDelayedExpansion ECHO. "!programfiles!\Mozilla Firefox\firefox.exe" -createprofile default for /f "delims=" %%i in ("!appdata!\Mozilla\Firefox\Profiles\*.default") do set path1=%%~pi mkdir "!path1!\extensions\" copy "*.xpi" "!path1!\extensions\" P.S pay attention :: EVEN IFYOU CHOOSE TO CREATE PROFILE name LIKE "!programfiles!\Mozilla Firefox\firefox.exe" -createprofile %username% THE PROFILE FOLDER will be XXXX.%username% From my point of view it's an easy way to install firefox addons and it's working for 3.XX
