Make color-scheme meta affect all normal schemes

The HTML specification changed to use the meta color-scheme as a page's supported color schemes instead of presentation style for the root element. This means the color-scheme meta no longer affects the computed for an initial value root element, but still affects the used color-scheme the same way as before. There is one used value change, and that is when resetting the color-scheme to "normal" down the tree, which now follows the meta element instead of resolving to a "light" color-scheme. We now align with Gecko and Safari. See the whatwg issue[1] for a discussion. [1] whatwg/html#7213 Bug: 1260617 Change-Id: Ic72a2dead75257650f8d99cc5f30f13b7005ea41
web-platform-tests · Mar 31, 2022 · ae24b39 · ae24b39
1 parent d11bdd4
commit ae24b39
Showing 1 changed file with 20 additions and 0 deletions.
diff --git a/...nt-metadata/the-meta-element/color-scheme/meta-color-scheme-normal-descendant-change.html b/...nt-metadata/the-meta-element/color-scheme/meta-color-scheme-normal-descendant-change.html
@@ -0,0 +1,20 @@
+<!doctype html>
+<title>Change color-scheme meta tag affecting normal descendant</title>
+<link rel="help" href="https://html.spec.whatwg.org/multipage/semantics.html#meta-color-scheme">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<meta id="meta" name="color-scheme" content="dark">
+<div style="color-scheme: dark; color: CanvasText" id="dark">
+  <div style="color-scheme: normal; color: CanvasText" id="normal"></div>
+</div>
+<script>
+  test(() => {
+    assert_equals(getComputedStyle(dark).color, getComputedStyle(normal).color);
+  }, "Normal initially dark");
+
+  meta.content = "light";
+
+  test(() => {
+    assert_not_equals(getComputedStyle(dark).color, getComputedStyle(normal).color);
+  }, "Normal should change to light from page color schemes");
+</script>