On Windows XP SP2:
The first sentence of the "Criticism of MLM" section in Firefox 18.104.22.168 reads:
"The MLM model does not guarantee the success of any individual involved in this model. The success will depend primarily on amount of work done by the individual and is not a good model for mediocre persons."
In Internet Explorer 6.0.2900.2180, this sentence is completely missing. It does not even appear in the source code.