diff --git a/css/css-fonts/font-variant-alternates-03.html b/css/css-fonts/font-variant-alternates-03.html
index 4270e2e0d3c62d8..1027363726771e9 100644
--- a/css/css-fonts/font-variant-alternates-03.html
+++ b/css/css-fonts/font-variant-alternates-03.html
@@ -24,6 +24,7 @@
 	  font-family: fwf;
 	  font-size: 2em;
 	  line-height: 1.1;
+	  font-variant-alternates: character-variant(doesnt-exist) styleset(doesnt-exist);
   }
   .high {
 	 font-variant-alternates: stylistic(foo);
diff --git a/css/css-fonts/font-variant-alternates-06.html b/css/css-fonts/font-variant-alternates-06.html
index bbeca548f6392de..c3f315723cbbc8c 100644
--- a/css/css-fonts/font-variant-alternates-06.html
+++ b/css/css-fonts/font-variant-alternates-06.html
@@ -24,6 +24,7 @@
 	  font-family: fwf;
 	  font-size: 2em;
 	  line-height: 1.1;
+	  font-variant-alternates: styleset(doesnt-exist);
   }
   .high {
 	 font-variant-alternates: styleset(foo);
diff --git a/css/css-fonts/font-variant-alternates-09.html b/css/css-fonts/font-variant-alternates-09.html
index 7cc6a1a30aa12f2..2c67b1439e6de42 100644
--- a/css/css-fonts/font-variant-alternates-09.html
+++ b/css/css-fonts/font-variant-alternates-09.html
@@ -24,6 +24,7 @@
 	  font-family: fwf;
 	  font-size: 2em;
 	  line-height: 1.1;
+	  font-variant-alternates: character-variant(doesnt-exist);
   }
   .high {
 	 font-variant-alternates: character-variant(foo);
diff --git a/css/css-fonts/font-variant-alternates-12.html b/css/css-fonts/font-variant-alternates-12.html
index 12f1cc759555e81..0f2b9d317b95a41 100644
--- a/css/css-fonts/font-variant-alternates-12.html
+++ b/css/css-fonts/font-variant-alternates-12.html
@@ -24,6 +24,7 @@
 	  font-family: fwf;
 	  font-size: 2em;
 	  line-height: 1.1;
+	  font-variant-alternates: swash(doesnt-exist);
   }
   .high {
 	 font-variant-alternates: swash(foo);
diff --git a/css/css-fonts/font-variant-alternates-15.html b/css/css-fonts/font-variant-alternates-15.html
index becb4d40b80aa36..58a58d3cd153cdd 100644
--- a/css/css-fonts/font-variant-alternates-15.html
+++ b/css/css-fonts/font-variant-alternates-15.html
@@ -24,6 +24,7 @@
 	  font-family: fwf;
 	  font-size: 2em;
 	  line-height: 1.1;
+	  font-variant-alternates: ornaments(doesnt-exist);
   }
   .high {
 	 font-variant-alternates: ornaments(foo);
diff --git a/css/css-fonts/font-variant-alternates-18.html b/css/css-fonts/font-variant-alternates-18.html
index 8dfe0b8650319c2..26e1ecd0c222260 100644
--- a/css/css-fonts/font-variant-alternates-18.html
+++ b/css/css-fonts/font-variant-alternates-18.html
@@ -24,6 +24,7 @@
 	  font-family: fwf;
 	  font-size: 2em;
 	  line-height: 1.1;
+	  font-variant-alternates: annotation(doesnt-exist);
   }
   .high {
 	 font-variant-alternates: annotation(foo);