Chrome Developer Tools was essential for building and debugging this extension. Its features like real-time CSS editing, JavaScript debugging, and extension manifest validation made development much more efficient. The DevTools elements panel was particularly useful for implementing and testing the brightness adjustment features.
Chrome Developer Tools was invaluable during development for debugging, testing, and optimizing the extension. The ability to inspect elements, monitor performance, and test in real-time made building a seamless YouTube integration possible.
Adjust page brightness 
YT Speed Controller
Bookmark Assistant