Post your bugs, new features, or changes in OS X Yosemite Beta 3 you have noticed. I'll try to keep this post updated... Changes: Quicktime has a new updated icon. Dark can now be accessed via System Preferences Known Issues: iMovie and Final Cut Pro X will not work with Developer Preview 3. PhotoStream may not be functional in Aperture. Only the latest versions of iPhoto and Aperture will work on this Developer Preview. Canceling an update in the Mac App Store will prevent that update from being installed at a later time. To fix this restart the system and try again. Text in the WiFi Menu extra may not be visible in Dark mode.