2 files changed, 48 insertions, 0 deletions
diff --git a/testing/web-platform/tests/css/compositing/isolation/animation/isolation-no-interpolation.html b/testing/web-platform/tests/css/compositing/isolation/animation/isolation-no-interpolation.html
new file mode 100644
index 0000000000..666fb5358f
--- /dev/null
+++ b/testing/web-platform/tests/css/compositing/isolation/animation/isolation-no-interpolation.html
@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<link rel=author href="mailto:jarhar@chromium.org">
+<link rel=help href="https://drafts.fxtf.org/compositing/#isolation">
+<link rel=help href="https://drafts.csswg.org/css-transitions-2/#transition-property-property">
+<link rel=help href="https://github.com/w3c/csswg-drafts/issues/4441">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/css/support/interpolation-testcommon.js"></script>
+
+<body>
+<script>
+test_no_interpolation({
+  property: 'isolation',
+  from: 'initial',
+  to: 'isolate'
+});
+</script>
diff --git a/testing/web-platform/tests/css/compositing/isolation/blend-isolation.html b/testing/web-platform/tests/css/compositing/isolation/blend-isolation.html
new file mode 100644
index 0000000000..d1aa412ecf
--- /dev/null
+++ b/testing/web-platform/tests/css/compositing/isolation/blend-isolation.html
@@ -0,0 +1,31 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>CSS Compositing and Blending: isolation applied to a group containing blending</title>
+    <link rel="author" title="cabanier" href="mailto:cabanier@adobe.com">
+    <link rel="help" href="http://www.w3.org/TR/compositing-1/#isolation">
+    <meta name="assert" content="Isolation on a group with blending">
+<style>
+.a {
+  background-color: rgb(0,255,0);
+}
+#b {
+  width: 200px;
+  height: 210px;
+}
+.c {
+  width: 100px;
+  height: 100px;
+  mix-blend-mode: difference;
+}
+#d {
+  isolation: isolate;
+}
+</style>
+<p>Test passes if you see a solid green rectangle</p>
+<div id="b" class="a">
+  <div id="d">
+    <div class="a c"></div>
+  </div>
+</div>
+</html>