When loading a data source in an iframe, the galaxy js is doing some sort of invalid probing of the frame, leading to this error: Blocked a frame with origin "http://pk:8080" from accessing a frame with origin "https://tcga1.kilokluster.ucsc.edu". pk:8080 is the galaxy frame. Here is the offending code: jQuery( function() { $("iframe#galaxy_main").load( function() { $(this).contents().find("form").each( function() { What is this? And is there some way to work around it? On chrome it doesn't appear to cause any problem, however on FF it causes the js to abort in both frames, preventing the data source callback. b.c.