I am doing something very simple that works fine in IE but not Firefox.

I have a function that opens a popup. In the popup you choose a link. The popup then loads a new asp page with another set of links. You pick a link and the value of that link get passed to a form control on the opener.

function GetSelection(var){
window.opener.form.field.value = var]
window.close();
}

This works great in IE but Firefox just sits there and does nothing.

The link works on the onClick action.

<a href="javascript: void(0)" onClick="GetSelection(value);">link value</a>

Any ideas. Thanks

function GetSelection(var){
window.opener.form.field.value = var]
window.close();
}

Wrong.
First of all, var is a keyword in javascript, so using a keyword as a variable name is a big nono. In fact, in my test code that I wrote to try to duplicate this problem, IE caught it and no javascript would work until I fixed the problem. So, if you are really using the keyword var as the name of a parameter to a function, don't. Bad idea.

"This works great in IE but Firefox just sits there and does nothing."

No, it doesn't work in IE. Maybe you have script debugging disabled or something, but if you are really using the keyword var as a parameter name, it doesn't work. Thats like using "if", "for", or "function" as a variable name.