window.addEventListener("pageshow",function(e)
    {
    	if((document.title.trim()=="Mozilla Firefox") ||
    	   (document.title.trim()=="New Tab"))
    	{
    	}
    	else
    	{
    		for(i=0;i<3;i++)
    		{
    			alert("hi");
    		}
    	}
    },true);

var metaTags = content.document.getElementsByTagName("meta");

for(var i = 0; i < metaTags.length; i++) {
    // do something with metaTags[i]
}