A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
@Robin_Liang not sure what you are experiencing is global or if I have understood it correctly.
a. I am able to move my "Format cells" dialogue box.
b. If you are referring to resizing the "Format cells" dialogue box, then yes we can't do that.
c. If you are not able to move the "Format cells" dialogue box check if you have any other application open, try to close applications and reopen the excel and try.
if it still is not working kindly details to better understand your problem.
vish