I just tried it using "PiratePig", I'm right, it is milliseconds, but the default is 3 seconds (similar to
-Dsimulate-preloader=3000) if the define is enabled
On HTML5, I noticed that it continues, even if preloading has not completed at all. This means that it may be more helpful to use on the desktop (where there is no loading time), or to ensure the loading time is long enough that everything is loaded.
-Dsimulate-preloader and PiratePig works for me, but if another sample fails to work with
-final enabled, please let me know