window.open behaviour in chrome tabs/windows

Question

I have a small bit of javascript intended to open two or more tabs. This works fine in FF and IE, but chrome opens the second one in a new window instead of tab. It isn't dependant on the url as I've tried it with two identical url's. First opens in tab, second one in new window.

Here's my code snippet:

for(var i=0 ; i<sites.length ;i++)
{
    window.open(sites[i].Url);
}

Answer 1

Chrome automatically opens a URL in a new tab only if it's user generated action, limited to one tab per user action. In any other case, the URL will be opened in a new window (which, BTW, is blocked by default on Chrome).
window.open must be called within a callback which is triggered by a user action (e.g. onclick) for the page to open in a new tab instead of a window.

In your example, you attempt to open N tabs upon user action. But only the first one is opened in a new tab (because it's a user generated action). Following that, any other URL will be opened in a new window.

Similar question: force window.open() to create new tab in chrome (see answer by maclema)

Answer 2

I came across this question What is the (function() { } )() construct in JavaScript? which gives explanation on IIFE. I think this can be used over. Please bear with me I don't have deep knowledge about javascript. But I tried as below and its working.

var sites = [{"url" : "http://www.google.com"} , {"url" : "http://www.yahoo.com"} , {"url" : "http://www.msn.com"}];
console.log(sites);
for( var i=0 ; i < sites.length ;i++) {
    (function(i) {
        console.log(i);
        window.open(sites[i].url , "_blank");
    })(i);
}   

It opens the url in new tabs in chrome.