diff --git a/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-computed.html b/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-computed.html
index 163a740103c0e..e76d8564fe5aa 100644
--- a/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-computed.html
+++ b/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-computed.html
@@ -14,7 +14,7 @@
 test_computed_value("text-spacing-trim", "auto");
 test_computed_value("text-spacing-trim", "normal");
 test_computed_value("text-spacing-trim", "space-all");
-test_computed_value("text-spacing-trim", "trim-auto");
+test_computed_value("text-spacing-trim", "trim-both");
 test_computed_value("text-spacing-trim", "trim-all");
 test_computed_value("text-spacing-trim", "trim-start");
 test_computed_value("text-spacing-trim", "space-first");
diff --git a/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-invalid.html b/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-invalid.html
index 9f835352b286d..ca10d4ea13d8d 100644
--- a/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-invalid.html
+++ b/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-invalid.html
@@ -16,6 +16,7 @@
 test_invalid_value("text-spacing-trim", "auto space-all");
 test_invalid_value("text-spacing-trim", "auto space-first");
 test_invalid_value("text-spacing-trim", "allow-end");
+test_invalid_value("text-spacing-trim", "trim-auto");
 test_invalid_value("text-spacing-trim", "allow-end space-first");
 test_invalid_value("text-spacing-trim", "space-first allow-end");
 </script>
diff --git a/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-valid.html b/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-valid.html
index a83a099480d2b..9bd0ff071f6ba 100644
--- a/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-valid.html
+++ b/testing/web-platform/tests/css/css-text/parsing/text-spacing-trim-valid.html
@@ -13,7 +13,7 @@
 test_valid_value("text-spacing-trim", "normal");
 test_valid_value("text-spacing-trim", "auto");
 test_valid_value("text-spacing-trim", "space-all");
-test_valid_value("text-spacing-trim", "trim-auto");
+test_valid_value("text-spacing-trim", "trim-both");
 test_valid_value("text-spacing-trim", "trim-all");
 test_valid_value("text-spacing-trim", "trim-start");
 test_valid_value("text-spacing-trim", "space-first");