UPDATE I just read that extensions.ini
is not important at all and is automatically generated. So I guess I am wrong here, also given the [HKEY_LOCAL_MACHINE\SOFTWARE\MozillaPlugins]
key as mentioned by @routeNpingme. I'll remove this later today; just leaving it here to ensure others don't waste their time on the same thing.
Given the fact that Firefox allows for using different profiles, each with their own extensions, I never thought that it would use the registry as well. (Firefox being cross-platform makes me even wonder more about that, especially as Firefox already has it own kind of cross-platform mechanism of storing settings.)
So unless you're sure it's in the registry, you might want to peek into the Files and folders in the profile, especially extensions.ini
.
UPDATE
extensions.ini
Lists folders of installed extensions and themes. The file is automatically generated by nsExtensionManager and is used by low-level code to detect chrome packages and XPCOM components provided by installed addons. Can be deleted to resolve various issues.
(See command line arguments to start Firefox with another profile.)