How can I avoid syncing custom directory icons?

Custom directory icons can be set in the Finder by opening the Info panel (from the main menu View > Get Info, or by pressing Command-I) and dragging an image onto the icon on the top left of the Info panel. A custom icon can be removed again by clicking it in the Info panel and pressing the Delete key.

A custom directory icon is saved inside the directory itself as a hidden file named “Icon\r”, where “\r” stands for the carriage return character and is displayed in the Finder as a “?” character.

Hint: you can toggle the display of hidden files in the Finder with the keyboard shortcut Command-Shift-.

Even if custom file icons are hidden in the Finder, simply excluding hidden files in SyncTime will not exclude custom directory icons from a sync. If you want to exclude custom directory icons, you can add a Filename filter with the text “Icon”. Don’t use the text “Icon?” as seen in the Finder because, as mentioned, the ? character is only displayed by the Finder and not a part of the icon file name; instead, the “Icon” text will match any filename that contains that word, including “Icon\r”.