This extension allows you to add custom effects on window focus/blur. By default it adds a clutter desaturation and an opacity effect. You can however customize these effects by editing a file named ~/.ffxrc.json and then switching off and on the extension in gnome-tweak-tool.
To install, simply clone this repository and put 'focus-effects@paradoxxx.zero.gmail.com/' in ~/.local/share/gnome-shell/extensions. Or you can add it with gnome-tweak-tool.
Copyright (C) 2011 Florian Mounier aka paradoxxxzero
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.