Gotcha, but I'm still confused. Where do these channel names come from? The docs say "Tagging a channel as 'HTML5 / Playable in browser' needs to be done from the itch.io Edit game page, once the first build is published", but in the edit game page there's nothing like "channels".
Is there any "butler for dummies" tutorial out there? I really have a lot of questions and I can't find any well-explained resource. :(