Brave Browser’s New Fingerprinting Defense Changes Online Privacy (youtube.com)
Brave replaced info about your specific computer (always has been available to browsers) with a string of generic text. Everyone using Brave Browser provides the same number now. The new Brave removes descriptors, simply blanking them out.
WebGL is needed by websites so Brave can't just block it or remove it, because websites wouldn't work for you. Instead Brave injects randomization/noise into this extension list (ie tracker sees a scrambled list of trackers, history, etc).
EFF links to Cover Your Tracks, you can visit it to see what info your browser gives up about you.