Revise existing reftest for the changed treatment of symbols; also add a WPT reftest for this behavior.

Depends on D110223

Differential Revision: https://phabricator.services.mozilla.com/D110224

bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=1686512
gecko-commit: 61363611f751aa82c6cb797108ae1044dbf85899
gecko-reviewers: emilio
diff --git a/css/css-pseudo/first-letter-005-ref.html b/css/css-pseudo/first-letter-005-ref.html
new file mode 100644
index 0000000..4e9b962
--- /dev/null
+++ b/css/css-pseudo/first-letter-005-ref.html
@@ -0,0 +1,22 @@
+<!doctype html>
+<html>
+<head>
+    <meta charset="utf-8">
+    <title>CSS Reference: ::first-letter formatting</title>
+    <style>
+        div {
+            font-size: 36px;
+        }
+        span {
+            color: green;
+        }
+    </style>
+</head>
+<body>
+    <p>Test passes if the "$", "(&pound;)", "&#x20B9;" and "&copy;" symbols are green.</p>
+    <div><span>$</span>1,234.56</div>
+    <div><span>(&pound;)</span>78.90</div>
+    <div><span>&#x20B9;</span>10,000</div>
+    <div><span>&copy;</span>2021</div>
+</body>
+</html>
diff --git a/css/css-pseudo/first-letter-005.html b/css/css-pseudo/first-letter-005.html
new file mode 100644
index 0000000..60e36ea
--- /dev/null
+++ b/css/css-pseudo/first-letter-005.html
@@ -0,0 +1,26 @@
+<!doctype html>
+<html>
+<head>
+    <meta charset="utf-8">
+    <title>CSS Test: ::first-letter formatting</title>
+    <link rel="author" title="Jonathan Kew" href="mailto:jkew@mozilla.com">
+    <link rel="match" href="first-letter-005-ref.html">
+    <link rel="help" href="https://drafts.csswg.org/css-pseudo-4/#first-letter-pseudo">
+    <meta name="assert" content="Checks that symbols such as currency signs have proper ::first-letter styling.">
+    <style>
+        div {
+            font-size: 36px;
+        }
+        div::first-letter {
+            color: green;
+        }
+    </style>
+</head>
+<body>
+    <p>Test passes if the "$", "(&pound;)", "&#x20B9;" and "&copy;" symbols are green.</p>
+    <div>$1,234.56</div>
+    <div>(&pound;)78.90</div>
+    <div>&#x20B9;10,000</div>
+    <div>&copy;2021</div>
+</body>
+</html>