How do I change the highlight color in survey mode?

I have two screens, so I have one in the develop module and the other display has a survey mode window open. In the past, the currently-being-developed photo is bordered in white and it is easy to pick it out. The latest update uses an extremely narrow mid-grey border with a light grey background. When I look very, very carefully, I can pick out which one "has focus" (is the primary selection). I do not like having to put so much concentration into determining which photo has primary focus. I like the white border much better. Better still would be a selectable color. So, please, do not tell me that I must live with a two pixel wide border that closely resembled the background color. Tell me how I can fix this. Thank you so much!

P.S. if you can't tell which image is selected below, it's the lower left. And, yes, I can look at the "film strip" in the develop module, but sometimes I'm surveying a dozen or more images that are not all together on the film strip. I really want that white border back.