Hello we have strange 'black box' effect when dealing with large number of first level nodes. Here's screenshot - http://img188.imageshack.us/img188/1912/blackbox.png This problem appears only in firefox(3 stable and 3.5 beta aswell), in IE 7&8 everything is well. It seems like when total number of nodes to be rendered becames greater than some number every node above renders as black div. For example, screenshot was made with 1500 nodes and with 1000 nodes subset of this data no artifacts happens. Any suggestions?