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Mike Stern, User Experience Evangelist, Apple:

"… apps that use a Navigation Bar and have
a title also do a really good job of telling you
where you are. The title serves that purpose. …"
Designing Intuitive User Interfaces
(WWDC 2014, session 211)​

Chris Dreessen, AppKit Software Engineer:

"… This is a picture of Safari, and something
you're going to notice about it is that
the title of the window isn't there …"

2015-07-06 22-49-08 screenshot.png


Adopting Advanced Features of the New UI of OS X Yosemite
(WWDC 2014, session 220)​
 
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