Virtual Background Settings is not appearing using Meeting SDK

Meeting SDK Web
1

Description
Participants are unable to see or automatically apply a Virtual Background when joining a Zoom Meeting using the Web Meeting SDK.

Even though:

  • The signature token includes video_webrtc_mode: 1

  • updateVirtualBackgroundList() and setVirtualBackground() are executed

Participants do not get the Virtual Background applied automatically, and the Virtual Background UI does not appear for them.

I expected the SDK to apply the virtual background programmatically via
ZoomMtg.setVirtualBackground({ id: 'background-default' }),
but it is completely ignored for participants.

Browser Console Error

Which Web Meeting SDK version?

@zoom/meetingsdk: 4.1.0

Meeting SDK Code Snippets
Init + Join

ZoomMtg.setZoomJSLib(`https://source.zoom.us/${zoomVersion}/lib`, "/av");
ZoomMtg.preLoadWasm();
ZoomMtg.prepareWebSDK();
ZoomMtg.init({
  leaveUrl: directUrl,
  patchJsMedia: true,
  success: joinZoomMeeting
});

Virtual Background Logic

ZoomMtg.updateVirtualBackgroundList({
  vbList: virtualBackgroundLists,
  success: () => {
    ZoomMtg.setVirtualBackground({ id: 'background-default' });
  }
});

To Reproduce(If applicable)
Join a Zoom meeting as a participant (role = 0) via Web Meeting SDK

  1. SDK loads successfully

  2. updateVirtualBackgroundList() succeeds

  3. setVirtualBackground() is executed

  4. Participant joins meeting

  5. Participant video is still the real camera background

  6. No Virtual Background or it Settings appear

Device (please complete the following information):

  • Device: Asus VivoBook S15
  • OS: Windows 11
  • Browser: Chrome
  • Browser Version: 142.0.7444.176