I am working on two very similar books right now. In one book, all of my linked files display the blue chain link icon in the upper left corner of the frame. In the other book, none of the linked files display the blue icon. Both books use many linked graphics and files, and I am very curious as to why one book shows the link icon on all of the graphics, and one book does not show any link icons. Any ideas?
Different view settings in the documents...
First, the link icon can be turned on or off in layout view using View > Extras > Show/Hide Links Badge, or one file might be in either preview or overprint preview mode.
Thank you! It was actually Show Frame Edges that was not the same between documents. I had no idea that view settings were unique to each document, but you pointed me in the right direction. Thanks so much for solving this mystery!