In Chrome what is screen_capture_injected?

when i view the el开发者_StackOverflow中文版ements using chromes developers tools, in the BODY tag i see

screen_capture_injected=true

What does this mean? What does it do? I tried searching for it, but couldnt find anything.

In my case, I have installed the "Screen Capture" extension which I believe is the one adding this attribute.

It is a browser extension injection. I can be from any browser plug-in or extension. It allows newer browsers like chrome to do all the neat things to the web pages that we love (i.e., screen capture, Google voice links, greasemonkey editing, etc.)

Hope that clears it up.