User profiles created in Firefox 58 (and in future releases) are not supported in previous versions of Firefox. Users who downgrade to a previous version should create a new profile for that version. Learn about alternatives to downgrading on our support site. Install Firefox Extended Support Release. Firefox Extended Support Release (ESR) is an official version of Firefox developed for large organizations such as universities and businesses. Firefox ESR does not come with the latest features, but it does have the latest security and stability fixes.

I am trying to manually install the Google Widevine CDM plugin in Firefox 58.0.2 because the network does not allow redirects or software downloads from un-approved sources.

Firefox 58.0 Download For Android

I have used another computer on a unrestricted network to download the latest zip file from the redirector.govt1.com link I could find, and I have Google Chrome installed with the Google Chrome version of the Widevine plugin.

Firefox 58.02

I have tried creating a new profile, and tried dragging the zip file into a tab, I have tried manually installing it from options, and I have enabled debugging and tried to test install but got the errors with the manifest file. Any ideas on how to manually install the plugin?