What it is
A Manifest V3 extension that injects a panel into YouTube, alongside the player, while a video is running. Four tabs: Notes, Key Points, Analytics, Resources.
Notes are anchored to the video clock. Write one at 0:17 and it is filed at 0:17, so the list you leave with is a set of marks against the thing you were watching rather than a page of loose text.
The intended loop from there: pull the key points out of the video, combine them with whatever you wrote down, and generate a quiz from both. The quiz is the actual point. It is the step from having watched something to being able to recall it.
The real reason it exists
I wanted to learn Cursor. EduTube was the thing I built to learn it on.
It started in Claude 3.7 and moved into Cursor partway through, which meant picking up browser extension development, Manifest V3, GitHub and meta-prompting on the way. The extension was the excuse; the tooling was the lesson.
Where it is stuck
The Claude integration is meant to read the video content and produce summaries. Right now it returns Failed to fetch.
That is a browser extension problem more than an API problem. An extension’s permission model, its security boundary and a cross-origin request to an external service all have to line up, and one of them doesn’t. Everything downstream is blocked behind it: no summaries, no extracted key points, no quiz.
What does work
It installs, injects cleanly into YouTube’s page, and the sidebar framework is functional. Note-taking works. The tabs are there. It is a real running base with a hole in the middle of it.
What it has taught me so far
Integrating with a platform as complicated as YouTube is not a small job, and permissions and security want thinking about before you write anything rather than after. Error handling around an external API is not a finishing touch, it is the feature. And a panel living inside someone else’s page has to look like it belongs there, or it reads as malware.