1900488 - Setting color-scheme: light on iframe disables prefers-color-scheme media query in the framed document

Status: VERIFIED INVALID

(Core :: CSS Parsing and Computation, defect)

Description

[Tim Guan-tin Chien [:timdream] (please needinfo)]

STR:

Open test case:

data:text/html,<iframe style="color-scheme:light" src="data:text/html,<style>@media (prefers-color-scheme: dark) { body { background: rebeccapurple } }</style>">

Expected:

The iframe doc background color should be purple.

Actual:

The iframe doc background color is transparent.

Note:

The test case expands to

<iframe style="color-scheme:light" src="frame.html">

and in frame.html:

<style>
@media (prefers-color-scheme: dark) { 
    body {
        background: rebeccapurple
    }
}
</style>

Both Chrome and Safari shows purple background in this case.

Comment 1

[Emilio Cobos Álvarez [:emilio]]

This is a bug in Chrome and Safari, see https://github.com/w3c/csswg-drafts/issues/7493

Comment 2

[Tim Guan-tin Chien [:timdream] (please needinfo)]

Thanks Emilio!