[0.17.38] Deconstruction Planner Reserving Particular Inventory Slot

[otobot1]

I initially noticed that the landfill in my inventory was not sorting properly. A deconstruction planner was splitting the stacks of landfill into two different sections, as seen in screenshot1.
After playing around a bit, I noticed that it wasn't a particular deconstruction planner. I had 2 decon planners in my inventory, and they were both able to occupy the particular slot in my inventory, but it didnt matter which one. I then deleted both of the deconstruction planners by right clicking them and clicking the trash can in the upper right corner. But the slot was still reserved for a decon planner. See screenshot2.
Now that the decon planner in the slot was more transparent, I noticed that the slot in my inventory was blue like when a slot is reserved for a particular item in a chest, or a train, or the old inventory hotbars. So I clicked the slot with Mouse3 and the reserved slot went away and my inventory returned to normal. See screenshot3.

I have no idea how I managed to reserve a slot like that in my inventory and I haven't been able to reproduce it. I suspect it's user error, but I decided to make a bug report just in case. I'm having troubles uploading my save at the moment (error parsing server response) so that is not included.

[otobot1]

After playing around some more, it seems that I middle clicked on a random slot in my inventory and that reserved a spot for the deconstruction planner. Not a bug then, but is this intended behaviour? It seems strange that this can accidentally happen in an inventory that is set to be automatically sorted.

[tehfreek]

Yes, you can reserve arbitrary inventory slots, same as every other container with reservable slots.