UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36

Steps to reproduce the problem:
1. Open https://platform.experimental.slidewiki.org/presentationbroadcast?room=chromiumtestcase&presentation=/Presentation/1597/1597/ in chrome (tab 1)
2. Complete all requested steps of the application
3. Open a new browser tab  (tab 2) and paste the same url again (to create a peer-to-peer connection (data-channel + audio from tab 1 to tab 2))
4. Complete all requested steps of the application
5. Edit the HTML of tab 2 to include "<a href="mailto:email1@example.com?subject=test&text=test">to</a>" somewhere and save it
6. click the newly created "to" link
7. a popup opens up that states that the presenter closed the session (see this line for my implementation and call of this dialog: https://github.com/slidewiki/slidewiki-platform/blob/1dcab754ddec2112c41dbac7ade27b3a254f2f29/components/webrtc/presentationBroadcast.js#L430)

What is the expected behavior?
dataChannel.onclose is not triggered by a mailto anchor

What went wrong?
dataChannel.onclose has been triggered by a mailto anchor. Nevertheless, the data channel is still there and works as expected. So it's not closed.

Did this work before? No 

Does this work in other browsers? Yes

Chrome version: 63.0.3239.132  Channel: stable
OS Version: Fedora 27
Flash Version: 

I tried the same on Firefox: works as expected and without any issues.
Unfortunately I can't provide an easy demo - sorry for that.