I don't know if the '%20' vs. '+' issue has always existed, or if it's something that was inadvertently introduced with some change.

I personally wouldn't call it an "issue" because AFAIK* it's optional whether spaces should be escaped as %20 or +, and it's been that way for a long time. From URI's Changes file:

   2001-01-10   Gisle Aas <gisle@ActiveState.com>
 
   Release 1.10
 
   The $u->query_form method will now escape spaces in
   form keys or values as '+' (instead of '%20').  This also
   affect the $mailto_uri->header() method.  This is actually
   the wrong thing to do, but this practise is now even
   documented in official places like
   http://www.w3.org/TR/html4/interact/forms.html#h-17.13.4.1
   so we might as well follow the stream.

In reply to Re^2: How encode space into %20 in URI by haukex
in thread How encode space into %20 in URI by Anonymous Monk

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