To this day, the Microsoft Silverlight installer package that comes in the dmg download says NOTHING about what it installs on my system and where. No "read me" file, NOTHING. Just a generic package installer and my fingers crossed Microsoft doesn't install crap onto my system that causes instability and/or slowdown my CPU? I don't think so.
To this day, Silverlight stays OFF my computer. Trust Microsoft? Hahahaha... good one! Same idiots who bought out and borged Virtual PC back in the day and their first accomplishment was to screw op the code and have it cause a kernel panic to my entire system (which had literally NEVER happened before on that system, EVER).
Then after ruining Virtual PC for Mac, they discontinued it. Microsoft cost many small businesses a loss in competition for a product and lost time/revenue dealing with their ineptitude and greed.
And, THIS just scratches the surface. So, am I going to install Siverlight on my Mac when there's OPEN alternatives? HELL NO.