Stress factor in flash?

[ArcaneMX]

I have noticed that in certain stuations in flash, such as loading screens, a small dark green bar will appear for a fraction of a second. I have seen it happen several times, on different movies, each time appearing with a different size and position in the upper left area. Is this related to stress, or is it something else (It is not part of my movie(s), It just appears there).
Has anyone else seen this behavior in flash?

[hangalot]

not standard. must be something specific to your pc or movie

[senocular]

yeah, seems weird to me.

[ArcaneMX]

Hm... I've checked all my movies that have this behavior and none of them have graphics or objects resembling that green square, and it's not in any of my actionscript.

You know when you export a swf directly from the fla file, ctrl+enter? And how while the movie is playing, if you push ctrl+enter again, the movie restarts after a delay?

Well, if you have a loading screen, the movie will not load on the first export, the bar wil be at 100% to begin with, but if you push ctrl+enter again, it will show the bar going through the entire loading process. The square only appears then.