title: NSMutableAttributedString overrides NSForegroundcolor when NSLinkAttributeName
body: <p>I have a working <code>NSTextView</code>. It does show some text and when it sees a URL, it shows a hyperlink with blue foreground color. So far so good.</p>
  
  <p>Now I am interested in showing a custom color for the URL. So I am setting another attribute <code>NSForegroundcolor</code>. I noticed that when I set <code>NSLinkAttributeName</code>, it will always override the custom color with default blue color. If I remove the <code>NSLinkAttributeName</code>, it will show the link with the custom color. As soon as I add <code>NSLinkAttributeName</code> back, it turns back to default blue.</p>