The bootstrap-sass-rails is deprecated starting with version 220.127.116.11. There is an official Sass port of Bootstrap now which can be found within the twbs organization on GitHub:
You are recommended to upgrade your Gemfile to directly use bootstrap-sass from now on. Upgrading should be really simple, the differences between the gems are mostly in the namespacing.
Remove the twitter/ prefix from all your
Before: @import "twitter/bootstrap"; @import "twitter/bootstrap/modal";
After: @import "bootstrap"; @import "bootstrap/modal";
Before: //= require "twitter/bootstrap"; //= require "twitter/bootstrap/modal";
After: //= require "bootstrap"; //= require "bootstrap/modal";
Thank you for using bootstrap-sass-rails!