Fix deduping issue with dream snaps

Dream snaps are causing deduping issues on the fronts ... basically, if you have n dream snaps in a container, it considers n more urls past the 'show more' border to have been 'seen'. This fixes that.

CC @johnduffell @stephanfowler @rich-nguyen @phamann Could one of you please take a look? This is a PROD issue and we need to get it out ASAP.
I'm aware this is logically equivalent.