Yes you are right when I switch to linear mode it's OK. Sorry but I didn't knew that. Mystery solved.

I dont understand (I'm not english speaker). Even I refresh the page the error is the same (for firefox). I need to go now C U tomorow.

I think that there is a bug when watching some posts with firefox. The post orders are different for internet explorer. You can see it is the same address but there is a difference between the third...