[mediacapture-screen-share-extensions] Recognize safer & better-integrated web presentations in getDisplayMedia (#9)

jan-ivar has just created a new issue for https://github.com/w3c/mediacapture-screen-share-extensions:

== Recognize safer & better-integrated web presentations in getDisplayMedia ==
### Use case
A participant in a video conference (website A), can safely present slides in a presentation-website B open in another tab or window, without exposure to privacy risks from oversharing, or threats to the web’s [same-origin security model](https://developer.mozilla.org/en-US/docs/Web/Security/Same-origin_policy). This presenter can advance (next/previous) slides from within A or B.

Safety must be the default, and to the extent a user agent still offers unsafe choices (to pick an unsafe source or follow an unsafe link in a safe presentation) they are clearly distinguished with warnings from the user agent that they carry additional risks over and above the safe ones. Unsafe choices do not contain integration features.

### Proposal

Add a new [display-surface](https://w3c.github.io/mediacapture-screen-share/#dfn-display-surface):
* An `“isolated-browser”` [display surface](https://w3c.github.io/mediacapture-screen-share/#dfn-display-surface) is the rendered form of a browsing context where the current top-level document is site-isolated and has opted into capture. Capture survives navigation to other pages that are also site-isolated and opted into capture. But upon any other navigation, the user agent MUST freeze capture on the last safe frame, and MAY prompt the user with a warning and option to allow capture of the unsafe content. Capture will resume once the browsing context is navigated back to safety, unless the user answered affirmatively to the prompt, in which case the source turns into a `“browser”` [display surface](https://w3c.github.io/mediacapture-screen-share/#dfn-display-surface).
 
Sources of this type MUST be given preferential placement in `getDisplayMedia()`’s picker over their unsafe counterparts.

Site-isolated pages that have opted into capture, can get an id that matches the id exposed on `“isolated-browser”` tracks (but unlike the [🔮 slide](https://docs.google.com/presentation/d/1fyRuFEqIsMrBg5KnfRxyH_2DRo3yudtOqI7ritpMUo0/edit#slide=id.gd97c219958_0_32), there's no requirement to register for preferential placement). This is to ensure that sites opt into building web-integrated capture-related features on this safer foundation, instead of the unsafe one we have today.


Please view or discuss this issue at https://github.com/w3c/mediacapture-screen-share-extensions/issues/9 using your GitHub account


-- 
Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config

Received on Friday, 23 February 2024 08:51:12 UTC