quoting attribute values is a hard habit to break

htmlminimizer.py

@@ -9,7 +9,7 @@ out = open(output_file, 'w', encoding="utf-8") # encoding argument! important!
 for line in open(input_file).readlines():
     # replace entities with Unicode characters
     for e in re.findall('&(.+?);', line):
-        if e in ('lt', 'gt', 'amp'):
+        if e in ('lt', 'gt', 'amp', 'nbsp'):
             continue
         n = html.entities.name2codepoint.get(e)
         if not n: