Interesting! So there are two problems here:
1) you end up in the tab one left. Does this behaviour change when you drag that mailto tab to the right? This would suggest some kind of bug in the "go back to the tab you came from"
2) capturing nothing -- this is from the desktop capturer, not the tab capture, right?

Hi,

1. Yes when I move to the other side it ends up to the right tab. Seems like "Go back to the tab you came from" is the case.
2. I guess it is desktop capture. I am not able to choose either to share the entire screen or a tab after clicking screen share. 

Thank you!

Ping!

1. Lowering priority because it's very unlikely for a typical end-user to ever execute these repro steps.

2. These repro steps are way too application-specific. Can you please distill it down into something small and generic? Otherwise, there is no way to rule-out whether this is a browser issue or a web site issue.

@miu: Thanks for your suggestions. 

@1 I agree this is not a very common practice. There is definitely a scenario which can break screen sharing in appear.in. 

@2: This is reproduced if we right click on mailto:xxx@xx.xx and open in a new tab. In new tab, perform a webrtc call in appear.in and share the screen. For some reason this blanks out the screen share for appear.in. This is applicable for all websites which contains that tab open. 

Note : This scenario is not reproducible in other browser. Thus I feel chrome is connected. It does not rule out the option of a appear.in bug too. 

@Fippo: Is this bug from appear.in screen share itself? Can you please provide your suggestion?

this is not under our control. It sounds like the mailto tab is not counted for some reason (because it has no valid url?).
Not getting a stream might be the result of running into an exception earlier or never getting an id for screensharing to feed into getUserMedia.

vasanthakumar:
https://github.com/webrtc/samples/tree/gh-pages/src/content/extensions/desktopcapture (visible from https://webrtc.github.io/samples/src/content/extensions/desktopcapture/) 
might be a way to reproduce this in a very small environment.
Hasn't seen much love recently though so the "how to get it to work" instructions might be outdated.

Thanks for for update Fippo. 

I was unable to download the extension. Thus I have to download similar from different location.

Step 1: Goto https://github.com/webrtc/test-pages/blob/gh-pages/src/peer2peer/extension/screencapture.zip. 
Step 2: After downloading extract the zip file. 
Step 3: Kindly update the weblink in manifest.json with "https://github.com/webrtc/samples/tree/gh-pages/src/content/extensions/desktopcapture". Save the file.
Step 4: Goto chrome://extensions
Step 5: Enable developer mode and load unpacked version. 
Step 5: Goto https://github.com/webrtc/samples/tree/gh-pages/src/content/extensions/desktopcapture and click Screen share. 

If  mailto:xxx@xx.xx or any other mailto page is open screen share is blank. 

This is reproducible 100% in the sample screen share too. 

Ping!