Lightroom 2015.6: Fullscreen Mode on Mac Disabled
In the release notes for LR 2015.6, it states that it fixes "inconsistent dialog behavior when using full-screen mode in Mac OS X 10.11." This may be the case, however it's been achieved at the cost of removing true fullscreen support from the application altogether. While it's still possible to enter a version of "fullscreen" by navigating to WINDOW -> SCREEN MODE, it's no longer possible to press the green button in the upper left hand corner of the application and position Lightroom in its own dedicated space in the OS. As such, LR is not running in true fullscreen mode -- it's still occupying the same "space" as the primary desktop / Finder, completely obscuring the desktop and creating usability issues when switching between open applications.