In the ZQuest main panel, on the bottom, between Favorite Combos and the screen's enemy list rectangle, there is the "Favorite Commands" panel. That is missing a few entries. Most of them consist of the entries in the "Tools" menu; namely, the Quest Reports tab.
That is an extremely important tab, and I find myself constantly using the "What links here?" entry in it. It's startlingly useful these days, I find. But it isn't listed as a command to be favorited in the list.