Variable font tests ensuring optical sizing corresponds to displayed size
diff --git a/css/css-fonts/variations/variable-opsz-size-adjust-ref.html b/css/css-fonts/variations/variable-opsz-size-adjust-ref.html
new file mode 100644
index 0000000..4e88cac
--- /dev/null
+++ b/css/css-fonts/variations/variable-opsz-size-adjust-ref.html
@@ -0,0 +1,31 @@
+<!DOCTYPE html>
+<html class="reftest-wait">
+<meta charset="utf-8">
+<style>
+ @font-face {
+ font-family: variabletest_box;
+ src: url(resources/variabletest_box.ttf);
+ }
+
+ body {
+ font-family: variabletest_box, sans-serif;
+ font-optical-sizing: none;
+ }
+
+ div {
+ line-height: 64px;
+ }
+
+</style>
+<div style="font-size: 9px; font-variation-settings: 'opsz' 9;">B</div>
+<div style="font-size: 18px; font-variation-settings: 'opsz' 18;">B</div>
+<div style="font-size: 36px; font-variation-settings: 'opsz' 36;">B</div>
+<div style="font-size: 72px; font-variation-settings: 'opsz' 72;">B</div>
+<div style="font-size: 96px; font-variation-settings: 'opsz' 96;">B</div>
+<div style="font-size: 36px; font-variation-settings: 'opsz' 128;">B</div>
+<div style="font-size: 72px; font-variation-settings: 'opsz' 12;">B</div>
+<script>
+ document.fonts.ready.then(
+ () => { document.documentElement.classList.remove("reftest-wait"); });
+</script>
+</html>
diff --git a/css/css-fonts/variations/variable-opsz-size-adjust.html b/css/css-fonts/variations/variable-opsz-size-adjust.html
new file mode 100644
index 0000000..b673f3c
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+++ b/css/css-fonts/variations/variable-opsz-size-adjust.html
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+<!DOCTYPE html>
+<html class="reftest-wait">
+<link rel="author" title="Dominik Röttsches" href="drott@chromium.org">
+<link rel="help" href="https://drafts.csswg.org/css-fonts-4/#font-optical-sizing-def"/>
+<link rel="help" href="https://drafts.csswg.org/css-fonts-5/#size-adjust-desc"/>
+<meta name="assert" content="Ensures that optical size is adjusted with size-adjust to displayed font size."/>
+<link rel="match" href="variable-opsz-size-adjust-ref.html">
+<meta charset="utf-8">
+<style>
+ @font-face {
+ font-family: variabletest_box;
+ src: url(resources/variabletest_box.ttf);
+ size-adjust: 150%;
+ }
+
+ body {
+ font-family: variabletest_box, sans-serif;
+ }
+
+ div {
+ line-height: 64px;
+ }
+</style>
+<!-- The variabletest_box font file contains a glyph for letter B which moves a
+ horizontal bar up from the middle for opsz > 12 and moves it down for opsz <
+ 12 where the opsz axis ranges from 6 to 128. -->
+<div style="font-size: 6px;">B</div>
+<div style="font-size: 12px;">B</div>
+<div style="font-size: 24px;">B</div>
+<div style="font-size: 48px;">B</div>
+<div style="font-size: 64px;">B</div>
+<!-- Explicit value overrides auto. -->
+<div style="font-size: 24px; font-variation-settings: 'opsz' 128;">B</div>
+<div style="font-size: 48px; font-optical-sizing: none;">B</div>
+<script>
+ document.fonts.ready.then(
+ () => { document.documentElement.classList.remove("reftest-wait"); });
+</script>
+</html>
