var notChangedStepsCount = 0;
var scrollInterval = setInterval(function() {
    var element = document.querySelector(".element-selector");
    if (element) { 
        // element found
        clearInterval(scrollInterval);
        element.scrollIntoView();
    } else if((document.documentElement.scrollTop + window.innerHeight) != document.documentElement.scrollHeight) { 
        // no element -> scrolling
        notChangedStepsCount = 0;
        document.documentElement.scrollTop = document.documentElement.scrollHeight;
    } else if (notChangedStepsCount > 20) { 
        // no more space to scroll
        clearInterval(scrollInterval);
    } else {
        // waiting for possible extension (autoload) of the page
        notChangedStepsCount++;
    }
}, 50);