Safari, and the resulting tabbed browsing, can revolutionize the way you work with the web. If you would like to keep the tabs in your browser, even if you don’t have a second tab (ie – if you’d like to test the size or look of your environment) then you can have the browser open with a single tab by default. com.apple.Safari.plist has a number of settings that aren’t exposed in the graphical interface of Safari. The AlwaysShowTabBar key can be used to set this behavior. For example: defaults write com.apple.Safari AlwaysShowTabBar -bool YES You can undo this with: defaults write com.apple.Safari AlwaysShowTabBar -bool NO