MediaDevices#getDisplayMedia(): systemAudio is misleading

MDN URL

https://developer.mozilla.org/en-US/docs/Web/API/MediaDevices/getDisplayMedia

What specific section or headline is this issue about?

systemAudio

What information was incorrect, unhelpful, or incomplete?

systemAudio constraint is misleading. Especially on Chrome or Chromium browsers, where window.speechSynthesisSpeak() called on the same Tab is not captured by navigator.mediaDevices.getDisplayMedia() using any constraints - because audio output as a result of a call to window.speechSynthesis.speak() really is output at the system level, not on the current Tab, or any browser Tab.

What did you expect to see?

A note notifying users that Chrome and Chromium browsers on Linux do not capture system audio.

Do you have any supporting links, references, or citations?

• https://github.com/GoogleChrome/developer.chrome.com/pull/3947#issuecomment-1274250421
• https://github.com/GoogleChrome/developer.chrome.com/issues/3957
• https://github.com/edisionnano/Screenshare-with-audio-on-Discord-with-Linux#enter-chromium
• https://github.com/guest271314/captureSystemAudio#references

Do you have anything more you want to share?

In spite of the specification using the terminology "systemAudio" Chromium and Chromium browser authors refuse https://bugs.chromium.org/p/chromium/issues/detail?id=931749 to support capture of system audio on Linux. Thus the constraint is misleading for user on Linux using Chrome or Chromium.

MDN metadata

• Folder: en-us/web/api/mediadevices/getdisplaymedia
• MDN URL: https://developer.mozilla.org/en-US/docs/Web/API/MediaDevices/getDisplayMedia
• GitHub URL: https://github.com/mdn/content/blob/main/files/en-us/web/api/mediadevices/getdisplaymedia/index.md
• Last commit: https://github.com/mdn/content/commit/2ba2c0efbdf0c34b1da02203e4e84b571c883629
• Document last modified: 2023-02-28T14:00:22.000Z