It's the UTF-8 encoding (0xC2 0xA0) of the non-breaking space (which is not included in the "whitespace" set of chars1 — thus your regex didn't match).

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1 update: at least not the iso-latin-1 encoding of the character, i.e. 0xA0  (for backwards compatibility, Perl assumes iso-latin-1 by default): 

print "\xa0" =~ /\s/ ? "space" : "no space";   # no space

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But see below.  Apparently, the 0xc2 part ("Â") somehow got lost in your case... — simply (incorrectly) treating the UTF-8 sequence as iso-latin-1 should have left you with two characters.

In reply to Re^3: Something strange in the world or Regexes by almut
in thread Something strange in the world or Regexes by mrguy123

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