diff --git a/layout/html/tests/css/max-height.css b/layout/html/tests/css/max-height.css
new file mode 100644
index 000000000000..29841fea3093
--- /dev/null
+++ b/layout/html/tests/css/max-height.css
@@ -0,0 +1,25 @@
+/*
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.0 (the "NPL"); you may not use this file except in
+ * compliance with the NPL.  You may obtain a copy of the NPL at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the NPL is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
+ * for the specific language governing rights and limitations under the
+ * NPL.
+ *
+ * The Initial Developer of this code under the NPL is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
+ * Reserved.
+ */
+
+
+GOOD :before { max-height: 3em } 
+GOOD :before { max-height: 15%; } 
+GOOD :before { max-height: none } 
+GOOD :before { max-height: inherit; } 
+BAD { max-height: babushka }
+BAD { max-height: auto; }
+BAD { max-height: 4px 4px; }
diff --git a/layout/html/tests/css/max-width.css b/layout/html/tests/css/max-width.css
new file mode 100644
index 000000000000..d016c935fb82
--- /dev/null
+++ b/layout/html/tests/css/max-width.css
@@ -0,0 +1,25 @@
+/*
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.0 (the "NPL"); you may not use this file except in
+ * compliance with the NPL.  You may obtain a copy of the NPL at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the NPL is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
+ * for the specific language governing rights and limitations under the
+ * NPL.
+ *
+ * The Initial Developer of this code under the NPL is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
+ * Reserved.
+ */
+
+
+GOOD :before { max-width: 10px } 
+GOOD :before { max-width: 15%; } 
+GOOD :before { max-width: none } 
+GOOD :before { max-width: inherit; } 
+BAD { max-width: babushka }
+BAD { max-width: auto; }
+BAD { max-width: 1in 1in; }
diff --git a/layout/html/tests/css/min-height.css b/layout/html/tests/css/min-height.css
new file mode 100644
index 000000000000..55cfb5e82eb1
--- /dev/null
+++ b/layout/html/tests/css/min-height.css
@@ -0,0 +1,25 @@
+/*
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.0 (the "NPL"); you may not use this file except in
+ * compliance with the NPL.  You may obtain a copy of the NPL at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the NPL is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
+ * for the specific language governing rights and limitations under the
+ * NPL.
+ *
+ * The Initial Developer of this code under the NPL is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
+ * Reserved.
+ */
+
+
+GOOD :before { min-height: 5pc } 
+GOOD :before { min-height: 15%; } 
+GOOD :before { min-height: none } 
+GOOD :before { min-height: inherit; } 
+BAD { min-height: babushka }
+BAD { min-height: auto; }
+BAD { min-height: 4px 10mm; }
diff --git a/layout/html/tests/css/min-width.css b/layout/html/tests/css/min-width.css
new file mode 100644
index 000000000000..3b98d29737c5
--- /dev/null
+++ b/layout/html/tests/css/min-width.css
@@ -0,0 +1,25 @@
+/*
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.0 (the "NPL"); you may not use this file except in
+ * compliance with the NPL.  You may obtain a copy of the NPL at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the NPL is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
+ * for the specific language governing rights and limitations under the
+ * NPL.
+ *
+ * The Initial Developer of this code under the NPL is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
+ * Reserved.
+ */
+
+
+GOOD :before { max-width: 5ex } 
+GOOD :before { max-width: 15%; } 
+GOOD :before { max-width: none } 
+GOOD :before { max-width: inherit; } 
+BAD { max-width: babushka }
+BAD { max-width: auto; }
+BAD { max-width: 5cm .5in; }