You can always explicitly send a header -- it doesn't look like you're doing that. CGI.pm makes it easy: 
print $q->header('text/html');

[download]
perldoc CGI for more on this. Or, you can send your header manually: 
print "Content-type: text/html\n\n";

[download]
Other than that, I'm not sure why the Mozilla browsers aren't rendering the code. Perhaps posting the contents of the $page variable or the *.rs files would help.

In reply to Re: Unexpected "text/plain" output with cgi by janjan
in thread [untitled node, ID 212629] by Samn

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