diff --git a/testsuite/css/parser/Makefile.am b/testsuite/css/parser/Makefile.am
index e9ab80f0e6..3120de0388 100644
--- a/testsuite/css/parser/Makefile.am
+++ b/testsuite/css/parser/Makefile.am
@@ -336,6 +336,8 @@ test_data = \
 	string-values.css \
 	string-values.ref.css \
 	test.png \
+	text-shadow-invalid-but-worked-in-3.12.css \
+	text-shadow-invalid-but-worked-in-3.12.ref.css \
 	transition.css \
 	transition.ref.css \
 	value-inherit.css \
diff --git a/testsuite/css/parser/text-shadow-invalid-but-worked-in-3.12.css b/testsuite/css/parser/text-shadow-invalid-but-worked-in-3.12.css
new file mode 100644
index 0000000000..7980f6d10a
--- /dev/null
+++ b/testsuite/css/parser/text-shadow-invalid-but-worked-in-3.12.css
@@ -0,0 +1,7 @@
+a {
+  text-shadow: inset 1px 1px;
+}
+
+b {
+  text-shadow: 0 0 0 0;
+}
diff --git a/testsuite/css/parser/text-shadow-invalid-but-worked-in-3.12.ref.css b/testsuite/css/parser/text-shadow-invalid-but-worked-in-3.12.ref.css
new file mode 100644
index 0000000000..e69de29bb2