Bootswatch simbol in chrome tab

A strange thing happen to my chrome web browser, and I don't know why, I hope you can help me.

In my chrome tabs the bootswatch symbol appears in the tab icon even when I'm not in the bootswatch website!!

I have already uninstalled the chrome browser using the AppCleaner.app, and I also checked if I had some weird extension installed.

I really don't know why this happens, it is strange. I am programming in ruby on rails and I have browsed and tried bootswatch, but I don't know why this has affected my browser!

Any help?