Ignore the pre selector when inlining CSS for incoming emails

This primarily addresses emails generated by Outlook, which can contain
thousands of <pre> tags that may cause performance issues. Since the default
pre selector typically only defines margins and fonts, ignoring it should
generally be acceptable.

Author: sunnavy

lib/RT/Interface/Web/Scrubber.pm

@@ -249,7 +249,7 @@ sub scrub {
 
     if ( ( length($Content) < ( 1024 * 1024 ) ) && $Content =~ /<style.*>/ ) {
         require CSS::Inliner;
-        my $css_inliner = CSS::Inliner->new( { encode_entities => 1, ignore_style_type_attr => 1 } );
+        my $css_inliner = CSS::Inliner->new( { encode_entities => 1, ignore_style_type_attr => 1, ignore_selectors => ['pre'] } );
         $css_inliner->read( { html => $Content } );
         $Content = $css_inliner->inlinify();
     }

lib/RT/Transaction.pm

@@ -381,7 +381,7 @@ sub Content {
             } else {
                 if ( ( length($content) < ( 1024 * 1024 ) ) && $content =~ /<style.*>/ ) {
                     require CSS::Inliner;
-                    my $css_inliner = CSS::Inliner->new( { encode_entities => 1, ignore_style_type_attr => 1 } );
+                    my $css_inliner = CSS::Inliner->new( { encode_entities => 1, ignore_style_type_attr => 1, ignore_selectors => ['pre'] } );
                     $css_inliner->read( { html => $content } );
                     $content = $css_inliner->inlinify();
                 }