仅限AFAIK desktopCapture API 支持音频+标签 。

AFAIK only desktopCapture API are supporting audio+tab.

chromeMediaSource 值必须 desktop 。

video: {
  mandatory: {                
      chromeMediaSource:'desktop',
      chromeMediaSourceId: 'sourceIdCapturedUsingChromeExtension'
  }
},
audio: {
  mandatory: {
    chromeMediaSource: 'desktop',
    chromeMediaSourceId: 'sourceIdCapturedUsingChromeExtension'
  }
}

在 Chrome-Canary 上试用以下演示：

• https://rtcmulticonnection.herokuapp.com/demos/Audio+ScreenSharing.html

• https://rtcmulticonnection.herokuapp.com/demos/Audio+ScreenSharing.html

但请务必启用 chrome：// flags＃tab-for-desktop-share flag。

However make sure to enable chrome://flags#tab-for-desktop-share flag.