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How do I install Icon themes?
Icon themes are a bit trickier. The GNOME Theme Manager does not install Icon themes into the correct location. Theoretically, Icon themes could be installed using the same method as Application and Window Border methods, but your Icon theme won't appear in the list if you use the "Install theme" button. So to install Icon themes, you may use either the Terminal or the Archive Manager methods mentioned in Question 1. Just be sure to use ~/.icons instead of ~/.themes. And clicking on the "Go to Theme Folder" in the Icon tab of the Theme Details window will take to the correct location for Icon themes