We may want to consider using the Java main thread as the FX application thread (that is, the GUI thread).

See RT-28574 for background information.

This would require Java launcher changes as well as work in the deploy toolkit on both the JRE and FX side and in the FX launcher. It may also invalidate tests that launch FX themselves and then do some test monitoring on the main thread (I think the media tests do this). For Mac, solving the -XstartOnFirstThread problem may make this difficult, especially since we need to interoperate with AWT.