630ec8b7_Appendix_D__X_Config_Options__Equipment
[Value] 2 [Equipment] 
"Blueline" glasses. These usually involve a passthrough cable between the monitor and video card. The glasses know which eye to display based on the length of a blue line visible at the bottom of the screen. When in this mode, the root window dimensions are one pixel shorter in the Y dimension than requested. This mode does not work with virtual root window sizes larger than the visible root window size (desktop panning).
Appendix D. X Config Options
Equipment