lightbox glitch or bug

This is a screenshot I took of an intermittent problem I'm experiencing when trying to view other people's photographs in lightbox mode.

I've reported it to ipernity, but so far they've been unable to reproduce the effect so are somewhat puzzled. So, I'm opening this up for comments to see if anyone else out there has experienced or is currently experiencing the same type of problem.

Here's a link to the photo I used for the screenshot:

www.ipernity.com/doc/dolladdictionuk/31660709