Google has been experimenting with a new UI for the YouTube player. The UI has transparent player controls that show you the relevant buttons without blocking the video.
The UI is still in development and hasn’t been finalized yet. But if you want to give it a shot, there is a way.
First you’d have to download the EditThisCookie extension for Chrome from the web store. Then head over to YouTube and click on the extension icon in your Chrome toolbar. Click “VISITOR_INFO1_LIVE” and then change the value to Q06SngRDTGA. After that, any YouTube video you open will have the new UI.
Since it involves a Chrome extension, this method only works on Chrome for now. Unless there is a similar extension for other browser that lets you make these changes, you’ll have to wait for whenever Google rolls out this design for everyone.