Index: web_ui.py
===================================================================
--- web_ui.py	(revision 5790)
+++ web_ui.py	(working copy)
@@ -62,14 +62,19 @@
     def get_supported_conversions(self):
         yield ('txt', _('Plain Text'), 'txt', 'text/x-trac-wiki', 'text/plain',
                9)
+        yield ('css', _('Style sheet'), 'css', 'text/x-trac-wiki', 'text/css',
+               9)
 
     def convert_content(self, req, mimetype, content, key):
-        # Tell the browser that the content should be downloaded and
-        # not rendered. The x=y part is needed to keep Safari from being 
-        # confused by the multiple content-disposition headers.
-        req.send_header('Content-Disposition', 'attachment; x=y')
+        if key == 'txt':
+            # Tell the browser that the content should be downloaded and
+            # not rendered. The x=y part is needed to keep Safari from being 
+            # confused by the multiple content-disposition headers.
+            req.send_header('Content-Disposition', 'attachment; x=y')
 
-        return (content, 'text/plain;charset=utf-8')
+            return (content, 'text/plain;charset=utf-8')
+        elif key == 'css':
+            return (content, 'text/css;charset=utf-8')
 
     # INavigationContributor methods