Screenshots in Chrome only work via SSL connection (). You can use a self-signed certificate and just accept it in your browser (this is for Chrome <M36).
In addition, for Chrome> M36 you should now use the Chrome.desktopcapture API and the usual way to change media restrictions and enable screen sharing inside Chrome will not work in newer versions of chrome.
The API is simple and MUCH is more robust than the previous option in media restrictions.
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