better useragent detection for CSS workarounds

This way gets it right when Tampermonkey is used.

src/General/Main.coffee

@@ -85,7 +85,7 @@ Main =
     return if !Main.isThisPageLegit() or $.hasClass doc, 'fourchan-x'
     # disable the mobile layout
     $('link[href*=mobile]', d.head)?.disabled = true
-    $.addClass doc, 'fourchan-x', 'seaweedchan', g.VIEW, '<% if (type === 'crx') { %>blink<% } else { %>gecko<% } %>'
+    $.addClass doc, 'fourchan-x', 'seaweedchan', g.VIEW, if chrome? then 'blink' else 'gecko'
     $.addStyle Main.css
 
     Main.setClass()