Twitch and Firefox, as well as some of the other flavors of Firefox such as the illusive Waterfox, are unable to activate Twitch extensions that ask for Twitch subscriber information. If you really want to activate it manually, you’ll need to do so from another browser such as Chrome or Edge.

However, even this isn’t needed as the Crowd Control extension will automatically activate itself when you click “Start Session”, as long as you have the “Automatically activate extension on session start” checked until Config -> Options in the Crowd Control desktop app.

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