@a_5mith, @julian
Well, not completely though.

You forgot to revert the hook-change in plugin.json:
https://github.com/rbeer/nodebb-plugin-youtube-lite/commit/ca010e57054a29632a1d400d6708f5bd20f53d31

The "error throwing" part of the com-message refers to
https://github.com/rbeer/nodebb-plugin-youtube-lite/blob/master/static%2Flib%2FlazyYT.js#L21

At that point I get ratio === undefined, yet width is also not given. Whereever this $el comes from there, it doesn't have .dataset.ratio, nor .dataset.width anymore.

plugin-ytlite-dataset.png

Can't explain why it's not showing in your ACP list. Didn't have any problems with that.

If it were working, would you prefer that Markdown hook over the post-parse one? Regarding downward compatibility, I'm hoping that there's a way to add hook handlers in an init function, isn't there? So you could check for Markdown and from there on set the appropriate hooks.