The page in question is www.davidclick.com . Yes whils that Javascript code did getthe grid layout consistent a FF bug got introduced in that dosplay:none was being added to the source code.
The situation now is no firefox bug but layout gappy with white space, oh dear…
If the page works with the scrpt in place and then occasionally you are getting a display:none added then how about trying to force the image to always be display:block.
I have no idea if this will make any difference but adding the script fixes the display issue immediately for me locally but I can’t reproduce your whole site to test
I’m sure the answer is in the script rather than css but try what I suggest and see what happens.
Thank You Paul your solution fixed a problem that was totally stressing me out. You generosity for taking time out to fix this is very much appreciated