# I built an AI-powered video speed controller for online courses > Source: > Published: 2026-07-22 05:32:24+00:00 I was taking 12 online courses in 3 months. Python, machine learning, web development — all while working full-time. Every platform had a different video player. Udemy's speed control had 4 steps. Coursera's shortcuts were different. LinkedIn Learning didn't remember my settings. I was spending more time fighting the players than actually learning. So I built CourseSpeed. CourseSpeed is a Chrome extension that gives you: **Chrome's MV3 migration is painful but worth it.** Service workers replace background pages, and the new API surface takes time to learn. **Course platforms don't want you to control speed.** Most of them strip or override custom speed controls. Getting CourseSpeed to work across Udemy, Coursera, LinkedIn Learning, and Skillshare required per-platform DOM manipulation strategies. **Science backs this up.** Murphy et al. (2022) found 2x speed causes no significant learning loss. Watching a lecture twice at 2x produces better retention than once at normal speed. I built CourseSpeed on this research — not assumptions. CourseSpeed just launched on Product Hunt and has active users on the Chrome Web Store. The most requested feature so far: per-platform speed presets (already built). If you take online courses and want to learn faster without losing comprehension, try it out: 👉 [https://joycraft.dev/coursespeed](https://joycraft.dev/coursespeed) Ask me anything about building Chrome extensions, the MV3 migration, or the science of video speed learning.