Pop up comment boxes (but not)

I was wondering if someone could look at the attached file and tell me how the designer of the sheet made it so the yellow comment boxes appear as they do...


thanks in advance,

josh

I don't know if you are still looking for info on this but here you go anyway. RoyUK is correct, it is data validation; the reason you don't see anything in the validation input message edit window is the cells are merged. If you unmerge the cells you can see the validation message for each cell. It shows up blank if you leave it merged but still works if you select the cell; and it looks like magic.