How can I prevent pop up windows created by either
window.showModalDialog from being blocked by the different browsers’ pop-up blockers?
The general rule is that popup blockers will engage if
window.open in response to a button click without getting hit by the popup blocker, but if you put the same code in a timer event it will be blocked. Depth of call chain is also a factor – some older browsers only look at the immediate caller, newer browsers can backtrack a little to see if the caller’s caller was a mouse click etc. Keep it as shallow as you can to avoid the popup blockers.