Hi Arthur,
I’m having the same problem, Twitch support is refusing me the extension upload because they see a bug in the configuration option, something that works perfectly in Hosted and Rig.
Initially, I’m asking for the configuration through the API and everything is fine, but Discord has recommended me to get the information through the helper and I’m getting the same as you.
My extension is made in Vue and I am executing the onChanged inside the mounted cycle.
whenever I try to obtain a configuration value I get back undefined.
Did you manage to solve it?