Originally created by Skillbert from RuneApps.org - https://runeapps.org/forums/profile.php?id=2
See: https://runeapps.org/forums/viewtopic.php?pid=5473#p5473
Great news - I've taken a look at the old YouTube app and got the app back in action with some simple fixes.
You can now access the new YouTube app using the following link: alt1://addapp/https://nigel1992.github.io/Alt1-YouTube-App//appconfig.json or use the link https://nigel1992.github.io/Alt1-YouTube-App/ in Alt1 Browser, and click ADD APP.
(Simply paste into your browser's navigation bar and hit ENTER)
For more info, please go to https://runeapps.org/forums/viewtopic.php?pid=5473#p5473