There was a time when Gecko used to allow HTML entities without the trailing semicolon. (I don't know what the current parsing rules are here.) That meant that if you had a form parameter named e.g. "macroname" then tried to use it in a hardcoded link e.g. "update.php?action=delete¯o=test" the ¯ would get interpreted as a ¯ character.
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"There was a time".
I'm guessing that goes way back. Even before people switched from HTML4 to XHTML doctypes.
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There was a time when Gecko used to allow HTML entities without the trailing semicolon. (I don't know what the current parsing rules are here.) That meant that if you had a form parameter named e.g. "macroname" then tried to use it in a hardcoded link e.g. "update.php?action=delete¯o=test" the ¯ would get interpreted as a ¯ character.