Can't add new class to topic page elements using jQuery?


Sounds like you might want to consider the widget route.

Also consider this api method:

api.reopenWidget("poster-name", {

      html() {

I would recommend you look at: A tour of how the Widget (Virtual DOM) code in Discourse works

It’s significantly more effort to do this kind of thing in Discourse because it is an auto-magical-web-app, but once you do it right, the solution can be very robust.