A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
I've noticed that if you have have linked images in other cells of the workbook, the drop down list created through data validation becomes weird. If you keep clicking on the cell it appear but vanishes when you move the mouse cursor. You have to right click and go to select from drop down and then it appears again briefly.
This has been a bug in Excel for a long time and It doesn't matter if you have Display All checked on the workbook options or if you check always visible. The crappy alternative around it is to use a combo box from the Developers tab.
I wish someone at Microsoft could do something about it instead of repeating the same threads.