As the title says. I can't even track down what mod is providing this feature, and it's causing some frustration as I press "r" to determine what Recipe the item under my mouse has, but the sort triggers first and gives me the recipe for another item sometimes.

The mod is called 'Inventory Profiles Next' and you can change it by going to your mod options and changing the hotkey for 'Sort Inventory'. Should be around the top of the hotkeys section.

Okay. I found the option and it's only accessible from the title screen... Sort of obtuse, but okay.