fix pool metatags, fix artist search

config/initializers/core_extensions.rb

@@ -2,7 +2,7 @@ module Danbooru
   module Extensions
     module String
       def to_escaped_for_sql_like
-        return self.gsub(/\\/, '\0\0').gsub(/(%|_)/, '\\\\\\1').gsub(/_/, '\\_').gsub(/\*/, '%')
+        return self.gsub(/\\/, '\0\0').gsub(/(%|_)/, "\\\\\\1").gsub(/\*/, '%')
       end
 
       def to_escaped_js