Since there is still no solution to this I wish to keep this question active as it is a major issue for me.  I use reference images a lot.

Reference images once imported disappear.  This is a recent issue since moving to the latest version.  The outline is visible but blank within.  The image will re-appear whenever an edit to the image is made (such as changing the layer or brightness etc.) but disappears again as soon as any other command is entered (pan, zoom, line ect.)

Thank you