EBS Auth & client credentials

No… It only requires ClientID.

curl -H “Client-Id: pxifeyz7vxk9v6yb202nq4cwsnsp1t” https://api.twitch.tv/kraken/extensions/uddfpjpm83bcj33vmxkyzf7m55o20q/live_activated_channels?api_version=5

Works fine.

Thats the ClientID from the docs and my ExtensionID. (But forcing API version via Query string)

curl -H “Client-Id: pxifeyz7vxk9v6yb202nq4cwsnsp1t” https://api.twitch.tv/kraken/extensions/uddfpjpm83bcj33vmxkyzf7m55o20q/live_activated_channels

Should result in a 404:

{“error”:“Not Found”,“status”:404,“message”:“”}

If you are using this end point make sure to set

Accept: application/vnd.twitchtv.v5+json

as a cURL header.

I envisage you are getting a 404 error not a 403 as a response?