Recently a user sent me a message saying that they could no longer click on a slicer item. I tried to myself and I had no issues clicking on the slicer item.
I then had an online screen share with the user, so that I could see what was happening when they were trying to click on the Slicer item. What had happened is they were using a lower screen resolution. What this did then was to place the Visual Header Icons over multiple lines, which then did not allow the top slicer item to be clicked on.
Click through for the solution.