If you would like to set a custom font icon in your menu from an icon set that you have loaded on your site, you can use the Custom Icon Class setting.
So for example, if your theme includes a camera icon that works like this:
<i class="my-camera-icon"></i>
then you can set the Custom Icon Class setting to my-camera-icon to add your custom icon to the menu.
Note that for this to work, your custom icons need to be able to work with the <i> tag. You may need to custom style your icons to fit with the menu, depending on how they are designed. You also need your icons resources to be loaded already (for example, by your theme) – this just adds markup to the menu, it doesn’t actually load your stylesheets and fonts for any icons.
This feature can also be used to add a custom class to an icon that already exists in UberMenu, that you can then use to style however you like.
Also note:
If you would like to use images as icons, you can upload an Image instead (the Icons feature is specifically for Font Icons)
If you would like to register a custom icon set to appear in the icon selection box, see Adding Custom Icons
Since version 3.2