Windows 7 had a similar effect for windows borders. It was actually cool. But Microsoft dropped it in favour of flatter opaque UI for Windows 8. I myself loved the translucency and Apple re-introducing this effect in Yosemite brings joy. Case being Microsoft dropped the ball... and Apple picked it up and polished it. Much has been said about Yosemite's UI. But I quite like it. Just wondering whether this glass effect is restricted only to Apple's native apps or can third party apps like Google's Chrome can make use of API's and have the same effect?