1 files changed, 22 insertions, 0 deletions
diff --git a/testing/web-platform/tests/css/css-env/at-supports.tentative.html b/testing/web-platform/tests/css/css-env/at-supports.tentative.html
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index 0000000000..c893f2dc54
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+++ b/testing/web-platform/tests/css/css-env/at-supports.tentative.html
@@ -0,0 +1,22 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <link rel="help" href="https://drafts.csswg.org/css-env-1/">
+    <title>Test that CSS env vars work with @support</title>
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <style>
+      @supports (background-color: env(test)) {
+        body { background-color: rgb(0, 128, 0); }
+      }
+    </style>
+  </head>
+  <body>
+    <script>
+    test(() => {
+      const style = window.getComputedStyle(document.body);
+      assert_equals(style.getPropertyValue("background-color"), "rgb(0, 128, 0)");
+    });
+    </script>
+  </body>
+</html>