No, this is not a real Sinatra error :).
This is the personal homepage of Elad Meidar, a web developer and an entrepreneur specializing in Ruby on Rails. I hang around in Israel, and i am currently having the best time of my life over at Fiverr.com
I am a proud member of RailsBridge, Helping new Rails developers get into our world and also contributed a few Patches to the Ruby on Rails core.
I have about 3000+ mail and i get something like 20-40 relevant messages a day, i usually very orgenized and i sort the incoming messages once an hour.
Now i had about unread messages that i missed in my inbox and wanted to find them, after a short quest i found this:
in the top search enter
<br />label:unread in:inbox<br />
and yaaa, all unread messages are found. you can drop the
in:inbox and get your entire list of unread messages, including other labels.
You're seeing this error because I think it is funny.