Suggestion: Add Highlighting and Note-Taking Tools

I've been using Khan Academy for several years, and I've always found their content to be informative and incredibly helpful. However, I believe it would be even more effective if there were a built-in note-taking feature—something that allows users to highlight key points and jot down notes directly within the platform for later review. This would be a significant time-saver, as I currently have to rely on external tools for digital note-taking. Manually copying information to another site is both time-consuming and inefficient.