The File Browser has some list on the left side showing system volumes and other shortcuts. Although those items have icons, there is a limitation in that you can only have one icon PER LIST. Every item in each list has the same icon.
This patch makes it so that each item in the "System" and "Volumes" lists can be added with unique icons. Therefore volumes can have different icons per drive type. And each System icon can be different, if desired, to better differentiate them. Like having a special icon for "Desktop" or "My Documents", etc.
Note that the above is a capture from my Windows machine after applying this patch. It does not show changes to Volumes icons because we don't have those new icons properly added to the project. They will be added soon: