First of all, thank you for using our extension! :) It is still in the alpha phase, so many things don't work as of now or are not implemented yet. We are currently working on getting more subpages to work, but the watch page should already be mostly functional... Also, I don't quite get what you mean with 720p and 480p, could you please create a more detailed report with some screenshots here: https://github.com/Cicero-Interactive/Classic-YouTube-Design/issues/? Thanks for your patience!