I am using HandyHands with Nullius. Nullius has "chirality" research which lets you combine some fluid buildings with a pipe to make an input-reversed version of the building. You can then combine the reversed version of the building with a pipe to make it back into the regular building.

HandyHands can decide that the way to make the regular building is to take a regular building, combine it with a pipe, take the resulting reversed building, combine it with a pipe... huh, we still haven't hit quota on the regular building, better do it again...

I submit, while vanilla Factorio doesn't exercise it, this is a bug in HandyHands because if it wants to make item X it should never consider a process that consumes as much item X as it will make.

So it's an issue that occurred before, but maybe with a slightly different cause now? Check the thread Continuously Crafting Wrong Item please. Also the previous fix was

• There's now a setting (defaults to off) for enabling autocrafting of recipes with multiple products.

So make sure that setting is off and hasn't been changed before we go further with this.

That setting is and was off (but additionally, neither of the involved recipes has multiple products, they're "building A + pipe -> building A-prime" and "building A-prime + pipe -> building A").

However, reading the linked discussion (especially the comment beginning 'HandyHands doesn't decide on a full "crafting path".') makes it clear it's a bit more complicated than I thought (and especially that HH isn't explicitly deciding to make building A by using up building A). I'll think it over and report back if I still think there's an infelicity in HH.