function popup4links() {
    // Fetch all the a elements in the document.
    var links = document.getElementsByTagName('a');

    // Loop through the a elements in reverse order
    // for speed.
    for (var i = links.length; i != 0; i--) {
        
        // Pull out the element for this iteration.
        var a = links[i-1];
        
        // If the element doesn't have an href, skip it.
        if (!a.href) continue;                

        // Set link target to _blank
        a.setAttribute('target', '_blank')
    }
}

registerPloneFunction(popup4links);