The good news for all Ubuntu Linux users, is that Canonical has just pushed the latest Mozilla Firefox 38.0 web browser to the main software channels of its supported Ubuntu OSes, including Ubuntu 15.04 (Vivid Vervet), Ubuntu 14.10 (Utopic Unicorn), Ubuntu 14.04 LTS (Trusty Tahr), and Ubuntu 12.04 LTS (Precise Pangolin). Earlier this month, we were happy to show you a first look at the number one feature of the Mozilla Firefox 38.0 web browser, the new tab-based preferences page.