[pointerevents] `MouseEvent.buttons` explanation of `contextmenu` event should mention about the platform dependency (#617)

masayuki-nakano has just created a new issue for https://github.com/w3c/pointerevents:

== `MouseEvent.buttons` explanation of `contextmenu` event should mention about the platform dependency ==
`MouseEvent.buttons` of [contextmenu event](https://w3c.github.io/uievents/#event-type-contextmenu) should mention about the platform dependency.

On Windows, context menu should be opened when mouse button is released. However, on the other platforms, it may be not. Therefore `buttons` won't contain the mouse button triggering to open the context menu on Windows, but may contain on the other platforms.

There is a note like:
> Depending on the platform, the [contextmenu](https://w3c.github.io/uievents/#contextmenu) event may be dispatched before or after the [mouseup](https://w3c.github.io/uievents/#mouseup) event.

But I think that this is not enough for `buttons`.

(Coming from https://bugzilla.mozilla.org/show_bug.cgi?id=1770671)

Please view or discuss this issue at https://github.com/w3c/pointerevents/issues/617 using your GitHub account


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Received on Monday, 12 January 2026 22:04:32 UTC