A little feature that if added would be more helpful

What I would like is a way in which you can bookmark lessons that you like and want to refer back to if you ever need them. I’m only a beginner at programming but I find that CSS Animations and various commands are things that I have to “relearn” at times. So, if this was added, I could easily relearn the topics without having to scroll down constantly just to find it. As of now, I haven’t found this feature anywhere on FreeCodeCamp so I just wanted to say that. Thank you and I hope to hear from you soon!