We seem to be having a terminology problem.
I’m not sure what YOU mean by “select the property”, as I thought that was what I was doing when I clicked in the editable field to the right of the word “Insets” in the properties tab.
My bad, I should have explained properly. I meant that when you click on the editable field, you do not have the option to right click on the same and click on Copy and Paste. Instead you can use the Ctrl+C and Ctrl+V to copy and paste.