If you're like me and switched over from Google Chrome looking for an equivalent extension to their Volume Master, this is definitely it. It's just as simple and effective as any native volume controls you'll encounter. Watching a stream and the streamer isn't loud enough for you? Turn it up. And you don't have to be afraid about switching tabs later to YouTube and forgetting that your volume is at 400% deafening yourself, because your YouTube tab will still be at the baseline 100%. It's also great that you can go below 100% as well. I don't know much about the dev, but since I rely on this extension so often, when they asked me for a review of it (which they hadn't pestered me at ALL about in the 7 months I've had it, unlike MANY other devs do for their products) I was more than happy to oblige. Get it and never look back.