An extremely simple SIMBL plugin to stop apps stealing focus.
At the moment the plugin is enabled for all apps, which is by no means ideal as it interferes with normal window swapping behaviour.
Install EasySIMBL with Homebrew:
brew install Caskroom/cask/easysimbl
Add a SIMBL plugins directory:
mkdir "~/Library/Application Support/SIMBL/Plugins"
Compile the Fookoff.bundle by opening Fookoff.xcodeproj and building. Then copy the compiled Fookoff.bundle to ~/Library/Application Support/SIMBL/Plugins.