QTWebEngine webRTC select device source

Hello Qt Development Team,

I am currently developing an Electron alternative framework based on PySide6 and am experiencing difficulties with screen-sharing functionality. Specifically, we need a feature in QtWebEngine that allows us to retrieve a list of available screens/windows along with source IDs for WebRTC streaming.

Unlike Google Chrome, which displays a screen selection dialog when `navigator.mediaDevices.getDisplayMedia()` is called, Chromium-based QtWebEngine does not open a selection window. This limitation makes it impossible to view or select available screens in a multi-monitor setup. Additionally, without a selection window similar to Google Chrome's, only one monitor can be streamed in a dual-monitor setup, restricting the choice of the desired screen.

The feature we aim to implement is similar to Electron's https://www.electronjs.org/docs/latest/api/desktop-capturer. It would be highly beneficial to have an API that provides a list of screens/windows and source IDs for connecting to WebRTC, enabling developers to implement a custom UI for screen selection.

If this feature could be added, it would significantly expand the possibilities for developing screen-sharing applications with QtWebEngine. It would also greatly benefit the community of developers creating diverse desktop applications using PySide6. Any information on the feasibility of adding this feature or recommended alternative approaches would be greatly appreciated.

Thank you very much.