What are “grid hotkeys”? I saw them in the preferences. What are they? How do they work?
Basically, it makes it so all units in a building, unit commands, etc. are assigned hotkeys based on their position in the UI. For example, since a Marine is the Top-Left in the Barracks, its hotkey would be Q. Here’s a page I found that has a small picture to illustrate: Grid Hotkeys.