diff --git a/testing/web-platform/tests/css/css-sizing/block-image-percentage-max-height-inside-inline.html b/testing/web-platform/tests/css/css-sizing/block-image-percentage-max-height-inside-inline.html
new file mode 100644
index 000000000000..2f6ad684c1fb
--- /dev/null
+++ b/testing/web-platform/tests/css/css-sizing/block-image-percentage-max-height-inside-inline.html
@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<link rel="author" title="Morten Stenshorne" href="mailto:mstensho@chromium.org">
+<link rel="help" href="https://www.w3.org/TR/css-sizing-3/#max-size-properties">
+<link rel="match" href="../reference/ref-filled-green-100px-square.xht">
+<p>Test passes if there is a filled green square and <strong>no red</strong>.</p>
+<div style="width:100px; height:100px; background:red;">
+  <span>
+    <!-- The image is a 1x1 transparent one. -->
+    <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" style="display:block; max-width:100px; height:1000px; max-height:100%; background:green;">
+  </span>
+</div>
diff --git a/testing/web-platform/tests/css/css-sizing/image-percentage-max-height-in-anonymous-block.html b/testing/web-platform/tests/css/css-sizing/image-percentage-max-height-in-anonymous-block.html
new file mode 100644
index 000000000000..5b1713975eb2
--- /dev/null
+++ b/testing/web-platform/tests/css/css-sizing/image-percentage-max-height-in-anonymous-block.html
@@ -0,0 +1,10 @@
+<!DOCTYPE html>
+<link rel="author" title="Morten Stenshorne" href="mailto:mstensho@chromium.org">
+<link rel="help" href="https://www.w3.org/TR/css-sizing-3/#max-size-properties">
+<link rel="match" href="../reference/ref-filled-green-100px-square.xht">
+<p>Test passes if there is a filled green square and <strong>no red</strong>.</p>
+<div style="width:100px; height:100px; background:red;">
+  <div></div>
+  <!-- The image is a 1x1 transparent one. -->
+  <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" style="max-width:100px; height:1000px; max-height:100%; background:green;">
+</div>
