You want:

$line =~ /\shref=(["'])?([^\s\>]+)\1/;
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No, that's not quite right, because he wants to find hrefs that are (probably) mistakes, stopping at the first space or > character. Something like this is closer, although I'm sure the regex gurus can improve on it:

  $line =~ /\shref=(["'])?(.+?)(?=[\s>]|\1|$)/;
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