Hi, I am resolving this bug as "won't fix", since starting Firefox 52 on April 18th the Screensharing whitelist is no longer needed to share your screen or windows. Please let us know if you find any problems! Much of this work was front-end, UX/UI changes, including support to let the UI know what streams are "scary" to share (see bug 1284910). See the meta bug 1127522 for all the work that went into this. Please read Jan-Ivar's blog post explaining the risks that users need to know about when sharing their screen or windows: https://blog.mozilla.org/webrtc/share-browser-windows-entire-screen-sites-trust/. The new UI permission dialog for screensharing links to a SUMO article with similar content to Jan-Ivar's post, but our SUMO team tailored it to a less technical user.