[csswg-drafts] [mediaqueries-5] `app-context` Media Query (#13932)

kyerebo has just created a new issue for https://github.com/w3c/csswg-drafts:

== [mediaqueries-5] `app-context` Media Query ==
Today, web developers do not have a reliable way to detect whether their app is running in an installed app window versus a normal browser tab. The closest existing signal is `display-mode`, but that reflects the current presentation mode rather than the application context, so it stops being reliable in cases like `fullscreen` or `minimal-ui`.

For example:
```css
.install-banner {
  display: flex;
}

@media (display-mode: standalone) {
  .install-banner {
    display: none;
  }
}
```
This works only until the installed app enters fullscreen. At that point, display-mode changes to fullscreen, the query no longer matches, and UI like install prompts can incorrectly reappear even though the user is still in the installed app experience.
The underlying issue is that “is this running in an installed app window?” and “what is the current display mode?” are orthogonal concepts, but the platform currently only exposes the latter.

I have an [app-context MQ Explainer](https://github.com/MicrosoftEdge/MSEdgeExplainers/blob/main/AppContextMediaQuery/explainer.md) which contains a proposal for tackling this issue. I'd love to get feedback on whether the shape looks correct, if the enumerated form is preferred, or anything else.

Please let me know if another venue (WICG?) would be a more appropriate place to socialize this. 
Thanks!

[Manifest GitHub Issue](https://github.com/w3c/manifest/issues/1092) | [CRBug with Developer Requests](https://issues.chromium.org/issues/331692948)


Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/13932 using your GitHub account


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Received on Friday, 15 May 2026 21:34:56 UTC