I use mac also, do you want to share a workbook with your phenomena to see if it is the same in my side?
I can't share that, however its happened on multiple workbooks. I tried turning off "automatic graphic switching" in the power options and haven't had the issue since then. I'll see if it shows up again. It might be a compatibility issue with the slower graphic card. I'll update this if it comes back.
I have the same issue - it has been like that in the last few versions. Sometimes it corrects itself if one refreshes data, but sometimes one need to close and open the workbook again to get rid of the blue boxes. It is very annoying and a waste of time.
Louise -- this thread went nowhere.
Start a new one. (Then, as the owner of your own thread, you'll be able to control closure of it when your problem is solved.)
And as you can see from this thread, people are going to need a sample workbook that demonstrates the problem. I pointed the owner of this thread to a link that shows how to anonymize your workbook if you are concerned about proprietary data, or hack up an example using superstore.
If you start a new thread without a workbook for this one, you can expect that no one will be able to help you without it.