Thanks to both of you. This worked.
For the benefit of MS workers who are likely lurking, I would add that this is poor layout of the function.
First of all, a second tab titled Layout appears at the end of the ribbon; at the same time, all of MS's instruction says, in the Layout tab" (and I'm looking for it in its usual spot fourth from the left) "click on the Data command group...."
Nowhere do the instructions say, "A second Layout tab will appear rightmost on the ribbon, with Table tools...." The average user is not looking for some faint, tiny new item that pops up at the far end of the ribbon.
Especially since instructions ask the user to look at Layout, and it's already in its usual place, fourth from the left.
It needs the simple fix of naming the contextual Layout tab (as opposed to the regular Layout tab) SOMETHING ELSE. Would dispel all this ambiguity.
I don't even do this for a living, and I'm surprised this janky business got through to production.