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diff --git a/testing/web-platform/tests/css/css-view-transitions/parsing/pseudo-elements-invalid.html b/testing/web-platform/tests/css/css-view-transitions/parsing/pseudo-elements-invalid.html
new file mode 100644
index 0000000000..5a2624d09d
--- /dev/null
+++ b/testing/web-platform/tests/css/css-view-transitions/parsing/pseudo-elements-invalid.html
@@ -0,0 +1,69 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>Test pseudo elements parsing of invalid selectors</title>
+<link rel="author" href="https://github.com/nt1m">
+<link rel="help" href="https://drafts.csswg.org/css-view-transitions-1/">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/css/support/parsing-testcommon.js"></script>
+<script>
+const functionPseudoElements = [
+    "::view-transition-group",
+    "::view-transition-image-pair",
+    "::view-transition-old",
+    "::view-transition-new",
+];
+
+function test_invalid_selector_combinations(pseudo) {
+    test_invalid_selector(`${pseudo}.a`);
+    test_invalid_selector(`${pseudo} div`);
+    test_invalid_selector(`${pseudo}:hover`);
+    test_invalid_selector(`:not(${pseudo})`);
+    test_invalid_selector(`:has(${pseudo})`);
+}
+
+test_invalid_selector_combinations("::view-transition");
+test_invalid_selector("::view-transition(*)");
+test_invalid_selector("::view-transition(valid)");
+test_invalid_selector("::view-transition(root)");
+
+for (const fn of functionPseudoElements) {
+    for (const validArgument of ["*", "valid", "root"]) {
+        test_invalid_selector_combinations(`${fn}(${validArgument})`);
+    }
+
+    // Test function without argument.
+    test_invalid_selector(fn);
+    test_invalid_selector_combinations(fn);
+
+    // Test function with empty argument.
+    test_invalid_selector(`${fn}()`);
+    test_invalid_selector_combinations(`${fn}()`);
+
+    // Test function with keywords excluded from <custom-ident>.
+    test_invalid_selector(`${fn}(default)`);
+    test_invalid_selector_combinations(`${fn}(default)`);
+    test_invalid_selector(`${fn}(unset)`);
+    test_invalid_selector_combinations(`${fn}(unset)`);
+    test_invalid_selector(`${fn}(initial)`);
+    test_invalid_selector_combinations(`${fn}(initial)`);
+    test_invalid_selector(`${fn}(inherit)`);
+    test_invalid_selector_combinations(`${fn}(inherit)`);
+    test_invalid_selector(`${fn}(revert)`);
+    test_invalid_selector_combinations(`${fn}(revert)`);
+    test_invalid_selector(`${fn}(revert-layer)`);
+    test_invalid_selector_combinations(`${fn}(revert-layer)`);
+
+    // Test function with multiple arguments.
+    test_invalid_selector(`${fn}(foo, bar)`);
+    test_invalid_selector_combinations(`${fn}(foo, bar)`);
+    test_invalid_selector(`${fn}(foo bar)`);
+    test_invalid_selector_combinations(`${fn}(foo bar)`);
+
+    // Test function with selector arguments.
+    test_invalid_selector(`${fn}(.foo)`);
+    test_invalid_selector_combinations(`${fn}(.foo)`);
+    test_invalid_selector(`${fn}(#bar)`);
+    test_invalid_selector_combinations(`${fn}(#bar)`);
+}
+</script>