Actually achieving vibrancy is fairly easy. You simply make the NSVisualEffectView the content view of the mac window. The issue with this is that it blurs the whole window, which is obviously not ideal. The way I see it there are couple different ways of going about this. There could be an API that allows you to create these VisualEffect views and then update their position and size. This may have issues with timing though, as things like element resizes would have to go through chromium to JS and then back to C++. Now this may prove to be negligible. The other solution would be to create a css property that can achieve this. This would prove to be harder. I am not completely sure where CSS is parsed, but a starting place may be the code behind -webkit-app-region. This seems like the most ideal way to implement this as it allows people to easily style their elements with it.