Ore Sorting Plant "pickup has no compatible sorting plant for mixed cargo"

Issue description

100% reproducible with the save file.
Transports won't always recognize a sorting plant as being compatible, even if all the correct materials are enabled for the plant, there is room for all of the materials and the plant's status is "waiting for products" and the truck is sitting right next to the plant.

Reproduction steps

I have an ore sorting plant that has iron ore, rock, soil and garbage enabled in it. Ore sorting plant's status is "waiting for products". All materials are empty or near empty. I have a truck that has ore, rock and soil in it, but reports it can't find a compatible sorting plant.

If I un-assign one of those 3 products from the sorting plant and assign it back immediately, suddenly the truck recognizes it as a compatible plant.

So far I've only seen it happen when the truck contains 3 products. So far I've only seen it happen a single time after loading a save and has not happened again until a save is loaded.

Load the save file.
Do not interact with the game.
Wait until late January of the next year.
You will see "pickup has no compatible sorting plant for mixed cargo". Pause.
Click on the alert to find the truck. It will be a short distance from a sorting plant. There's your culprit. Note that the first item in the truck's cargo is rock.
Remove rock the "products to sort". Add rock back to "products to sort". (Doing this for dirt or iron ore won't fix it. Presumably it has to do with the fact that rock has been loaded first into the truck.)
Unpause. The truck will now immediately find the plant and unload there.

Game version and build number

v0.7.6a (b466)

Operating system

Mac OS

Attachments

Save 2025-07-09, 11-20-33.save

Files not imported: Save 2025-07-09, 11-20-33.save

I have another save now, from a slightly later point in the game where I actually can't get the truck to accept the sorting plant no matter how I change the inputs on the sorting plant. I believe the difference is that this truck already contained this cargo and was in its stuck state when the save got created. The only way I could find the get the truck un-stuck is to use unity to force unloading it.

EDIT:
Never mind, this case is just me not realizing there was slag in there and I assumed it was the same problem.

He's got slag in the back, so he can't unload it anywhere.

@poltime you're right, this was unrelated to the bug I reported, thanks. The reported case is most definitely NOT involving slag, though.

In the first case, this is also not a bug. You don't have a sorting plant with rock and iron ore at the same time.

Well, I'll be. You're right. How silly. I suppose the rock and slag icons should be a bit more distinct!