2.3 Beta on OSX 10.10 Public Beta 6

[paultzirides]

I feel as though the performance on my DisplayLink-connected monitor has been significantly reduced. I'm using an Anker USB 3.0 Dock on the latest Yosemite beta (Beta 6), with a 1080p display connected using DVI. I have another display connected using Apple's Thunderbolt/Mini DisplayPort connector, which (naturally) works flawlessly.

Moving objects around the screen is incredibly slow, as is showing/hiding the dock, invoking Launchpad, or bringing up Mission Control. Windows on the DisplayLink-connected monitor also exhibit strange artifacts in the corners (top left, top right, bottom left, and bottom right).

Please address these issues, since it makes working with multiple displays very difficult.