If you are using reveal for thumbnail pop ups you may have noticed the screen jump when the modal opens. On a pc in Firefox and Chrome it's especially prevalent...

In your HEADER paste this fix:
I'll add this fix to the Step by Step Tutorial when I get the chance.
To see it work I have it on the example here: Thumbnail Pop Up
That now opens and closes with no screen jump.

That's a lot better.

A great fix thanks Alter Eagle for sharing

Thanks, that little jump was bugging me .