IsStandaloneContent does not work with `display: fullscreen` in Chrome Android

### MDN URL

https://developer.mozilla.org/en-US/docs/Web/Progressive_web_apps/How_to/Create_a_standalone_app

### What specific section or headline is this issue about?

_No response_

### What information was incorrect, unhelpful, or incomplete?

The `isStandaloneApp` code provided on that page is false when running in an installed fullscreen PWA app ([manifest display: fullscreen](https://developer.mozilla.org/en-US/docs/Web/Manifest/display#fullscreen)) in Chrome on Android.

Weirdly, this is true on Chrome Desktop, and using `window.matchMedia("(display-mode: fullscreen)").matches` is also false.

I wonder if this is a Chrome bug which I am happy to file if you confirm whether according to the spec, Chrome on Android should match `display-mode: fullscreen` OR `display-mode: standalone` in that case (and which one of those).

### What did you expect to see?

An isStandaloneApp function that works regardless of what's set in the PWA manifest `display`.

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

_No response_

### Do you have anything more you want to share?

_No response_

### MDN metadata

Page report details

* Folder: `en-us/web/progressive_web_apps/how_to/create_a_standalone_app`
* MDN URL: https://developer.mozilla.org/en-US/docs/Web/Progressive_web_apps/How_to/Create_a_standalone_app
* GitHub URL: https://github.com/mdn/content/blob/main/files/en-us/web/progressive_web_apps/how_to/create_a_standalone_app/index.md
* Last commit: https://github.com/mdn/content/commit/835d6632d59993861a0458510402787f8a2c3cb3
* Document last modified: 2023-10-25T17:27:32.000Z