@TeamYouTube Not sure if this issue is known but for the past week or so the comment section of mainly newer popular videos doesn't appear for me at times on both desktop and mobile. Have to set it to sort by 'New comments' first for it to load otherwise it remains blank.
We'd like to help. For desktop, please clear your browser's cache and cookies. Here's how: https://goo.gl/t2cwdF . For mobile devices, could you try uninstalling and reinstalling the app to see if that fixes the issue? Keep us posted.