Test of navigator.getDisplayMedia Screenshare

The purpose of this repository is to test the implementation of navigator.getDisplayMedia in MS Edge. It contains two different, condensed scenarios relying on the feature, and allows mocking navigator.getDisplayMedia with navigator.mediaDevices.getUserMedia.

Steps to prepare

1. Clone the repository and cd into it
2. Install dependencies using npm install

Replicating the issues

To compare the result with that of navigator.getUserMedia, toggle the flag USE_USER_MEDIA_AS_MEDIA_STREAM in ./public/local-stream.html:54 or ./public/rtc-stream.js:4.

Start the server

npm start

The port of the server can be configured through the PORT env variable, or by explicitly changing the PORT constant in ./server.js:15.

Basic test

Open https://localhost:8000/local-stream.html. You will need to confirm the use of self-signed certs. Try clicking "Share Screen".

Expected Result of Basic test

A video appears in the middle of the screen, reflecting the content of the getDisplayMedia MediaStream.

Outcome on Edge 42.17134.1.0 with EdgeHTML 17.17134

A MediaStreamError (AbortError) is thrown:

[object MediaStreamError]: { constraintName: null, message, null, name: "AbortError" }

This has been reported in Issue #17357055 on issues.microsoftedge.com.

Test with WebRTC streams

Open https://localhost:8000/rtc-stream.html in two different tabs. One of the tabs will be the reciever, and one the transmitter. You will need to confirm the use of self-signed certs. In one of the tabs,try clicking the "Share Screen" button. This is now the transmitting tab.

Expected Result

A video appears in the middle of the tab of the receiving tab, reflecting the content of the getDisplayMedia MediaStream.

Outcome on Edge 41.16299.15.0 with EdgeHTML 16.16299

The following error is consistently thrown the following at main.js:134:7 pointing to the start of the line adding the stream to the peerConn:

{
  "description": "Could not complete the operation due to error c004e001.",
  "message": "Could not complete the operation due to error c004e001.",
  "number": -1073422335,
  "stack": "Error: Could not complete the operation due to error c004e001. at Anonymous Function (https://x.x.x.x:8000/public/main.js:134:7)"
}

Outcome on Edge 42.17134.1.0 with EdgeHTML 17.17134

Same error as in the basic test for these versions (MediaStreamError - AbortError).

Assumptions made

1. Edge allows creating an objectURL for a MediaStream
2. Edge allows assigning an objectURL of a MediaStream as the src of an HTMLVideoElement
3. Edge supports relevant ES6 syntax
4. Edge does not treat websites on self-signed certificates differently than authorized certificates, once the user has confirmed entering the site.
5. Edge should not treat MediaStream of getDisplayMedia differently than that of getUserMedia. So far, I've found this assumption to be false.