The duplicate detector is a bit odd. Not sure what its rules are, but it doesn&#x27;t always seem to work. One example (only noticed this because I wrote the linked blog post.)<p><pre><code>  https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=8860103 : http:&#x2F;&#x2F;reactionwheel.net&#x2F;2015&#x2F;01&#x2F;80s-vc.html
  https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=8908463 : http:&#x2F;&#x2F;reactionwheel.net&#x2F;2015&#x2F;01&#x2F;80s-vc.html?newpost
  https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=8927285 : http:&#x2F;&#x2F;reactionwheel.net&#x2F;2015&#x2F;01&#x2F;80s-vc.html
  https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=9129911 : http:&#x2F;&#x2F;reactionwheel.net&#x2F;2015&#x2F;01&#x2F;80s-vc.html</code></pre>