I'm not sure if this is a bug, but don't see why it wouldn't be there.
In the screenshot, you can see the icon I've outlined in red doesn't appear on cutters.
The icon has a number by it (which I've cut out in the screenshot) to show how many buildings of that type are needed for a full belt.
Finding ratios is easy enough (belt speed divided by building speed) and you can mouse over the icons which are already there, but players who are new to these games could be thrown off with the icon not being there.
Mods - If this isn't a bug, please move this to feedback.
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