I no longer see a way to favorite a post, only follow the poster
If you mean favouriting an Instructable, that's a pro feature.
When did that become a pro feature? I have favorites I've set in the past. I hope they don't disappear now that I've brought your attention to them.
Sorry, my mistake - I've just used my non-pro son's account, he has favourites available.The button is a small heart-shape at the top-right of the project.