@Divingduck: Those are all non-standard css properties. You will be warned about any property not in the CSS 2.1 standard (plus a few from CSS 3). Extra CSS properties are usually harmless, so just ignore the warning, if you dont want to delete them.
@arspr: If you have modified text in an editor, all entities are automatically converted to unicode before checking, which is why you will not get message about them. Close and re-open the editor and you will see that.
I'm afraid the error messages come from the cssutils library, I really dont have the time/interest to make them more friendly. Patches are welcome.
You really should not be using style attributes, but remind me about it after the release and I will see if checking can be added for them.
The HTML 5 spec requires unclosed <i> tags to render the remaining text in italic, which is why you get an extra pair of <i> tags. It's a silly requirement, but it's in the spec, probably for legacy compatibility requirements. Try viewing the following html snippet in a modern browser,
Code:
<!DOCTYPE html>
<html>
<head>
<title>test</title>
<meta http-equiv="content-type" content="text/html; charset=utf-8"/>
</head>
<body>
<p>some <i>italic</p> after text will also be italic
</body>
</html>