Industrial Foregoing Version: 1.12-1.4
TeslaCoreLib Version: 1.12-1.0.12

If a machine is disabled via configs that is used as the icon for a grouping in the IF manual, then the manual doesn't have an image to use for the grouping. The manual should have some kind of fall back, such as picking the next available machine for the section or having symbolic icons for each section (think Botania).

In my case, I disabled the Petrified Fuel Gen, the Laser Base, and the Laser Drill, so the Generators and Resource Production sections have no icon.