Question

If write this:

        $(document).on("click", function () {
             window.scroll( 0, 70 );
        });

works always, but if write this:

        window.onload = function () {
             window.scroll( 0, 70 );
        }

this not works in safari and in “incognito window” for chrome. in other browsers works.
why?

Answer 1

In very simple terms, the main reason is the state of the different browser/dom elements you are binding to.

In the first one, you are binding to the click event on the <body/> using jQuery, which is possibly ensuring that by the time you get around to actually clicking it, the body of the document is initialised and has enough scroll left to make the effect appear to you.

In the second one, you are binding to the onload event of the window, which actually fires much before the body may have loaded, or accumulated enough scrollable area, thus making the effect to not appear.

The ideal technique instead would be to use

$(document).ready(function() {
    window.scrollTo(0,70);
});