How I Built a Browser Extension to Download Videos from Kinescope for Offline Learning
I travel a lot — trains, planes, long drives out of town. And I always want to use that time productively: read, listen to podcasts, or learn something new.
The problem is, internet connectivity on the road is rarely reliable. And many educational platforms use the Kinescope player, which doesn’t offer a built-in way to download videos for offline viewing.
Sure, you could open DevTools, find the .m3u8 playlist in the network requests, copy the link, fire up FFmpeg in the terminal… But doing that every single time — especially when there are dozens of videos — is tedious and eats into time better spent actually learning.
I wanted a simple solution: open the video page, click a button, and have everything ready for offline watching.
Why a Browser Extension?
I considered a few options: writing a parser script, using a download manager, or building a browser extension.
I went with an extension because it’s the most natural and convenient approach:
- It works right on the video page — no context switching.
- It can intercept the player’s network requests in real time.
- Everything is controlled with a single button. No extra steps.
The workflow is dead simple: open the lecture, click “Save,” move on to the next one. Repeat for all the materials I plan to watch on the road.
What I Built
The extension does two things:
- Intercepts all links to video and audio streams requested by the Kinescope player.
- Saves them to
Downloads/kinescope/[Video_Title]/along with metadata (title, duration, description).
A floating button appears on the page showing how many streams have been found. One click — and all the links are saved to your folder, neatly sorted by video and audio.
After that, I run a Python script that automatically stitches everything together using FFmpeg into a ready-to-watch .mp4 file. And just like that — a library of lectures ready for offline viewing.
The Result
Now preparing for a trip takes just a few minutes:
- Open all the videos I need → click the button on each page.
- Run one script → it processes everything automatically.
- Copy the finished files to my laptop or tablet and hit the road.
No DevTools, no manual copying of links. Just time well spent.
Project Link
The extension is open source and can be installed manually via developer mode in Chrome. All you need are four files from the repository:
👉 Kinescope JSON-LD Extractor PRO on GitHub 👈
Hope you find it useful.