Function to automatically zoom in any website to fill available screen width

expand_window.js

(function() {
  function expand($) {
    function text($element) {
      return $.trim($element.clone().children().remove().end().text());
    }

    function isFixedOrFloating($element) {
      try {
        if ($element.css("position") === "fixed") {
          return true;
        }

        var float = $element.css("float");
        if (float === "left" || float === "right") {
          return true;
        }

        var $parent = $element.parent();
        if ($parent.length) {
          return isFixedOrFloating($parent);
        }

      } catch (e) {
        return false;
      }

      return false;
    }

    function hasContent($element) {
      // Ignore elements that are deliberately positioned off-screen.
      var offset = $element.offset();
      if (offset.left < 0 || offset.left > $(document).width()) {
        return false;
      }

      // Ignore elements that float or are fixed to a set position on the screen
      // as these will remain in view after zooming.
      if (isFixedOrFloating($element)) {
        return false;
      }

      return $element.is(":visible") && text($element).length > 0;
    }

    function getExtremeEdges($elements) {
      var extremeLeft = null;
      var extremeRight = null;

      $.each($elements, function(i, el) {
        var $element = $(el);
        var offset = $element.offset();
        var left = offset.left;
        var right = offset.left + $element.width();

        if (!extremeLeft || left < extremeLeft) {
          extremeLeft = left;
        }

        if (!extremeRight || right > extremeRight) {
          extremeRight = right;
        }
      });

      return [extremeLeft, extremeRight];
    }

    var $elementsWithContent = $("*").filter(function(i) {
      return hasContent($(this));
    });

    var extremeEdges = getExtremeEdges($elementsWithContent);

    var width = extremeEdges[1] - extremeEdges[0];

    var desiredWidth = $(document).width() * 0.95;

    if (width < desiredWidth) {
      $("body").css("zoom", desiredWidth / width);
    }
  }

  function waitToExpand() {
    setTimeout(function() {
      if (typeof window.jQuery === "undefined") {
        waitToExpand();
      } else {
        expand(window.jQuery);
      }
    }, 100);
  }

  // Dynamically inject jQuery into the page if it's not already present.
  if (typeof window.jQuery === "undefined") {
    var script = document.createElement("script");
    script.type = "text/javascript";
    script.src = "https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js";
    document.body.appendChild(script);

    waitToExpand();

  } else {
    expand(window.jQuery);
  }

}());

expand_window.min.js

(function(){function a(a){function b(b){return a.trim(b.clone().children().remove().end().text())}function c(a){try{if(a.css("position")==="fixed"){return true}var b=a.css("float");if(b==="left"||b==="right"){return true}var d=a.parent();if(d.length){return c(d)}}catch(e){return false}return false}function d(d){var e=d.offset();if(e.left<0||e.left>a(document).width()){return false}if(c(d)){return false}return d.is(":visible")&&b(d).length>0}function e(b){var c=null;var d=null;a.each(b,function(b,e){var f=a(e);var g=f.offset();var h=g.left;var i=g.left+f.width();if(!c||h<c){c=h}if(!d||i>d){d=i}});return[c,d]}var f=a("*").filter(function(b){return d(a(this))});var g=e(f);var h=g[1]-g[0];var i=a(document).width()*.95;if(h<i){a("body").css("zoom",i/h)}}function b(){setTimeout(function(){if(typeof window.jQuery==="undefined"){b()}else{a(window.jQuery)}},100)}if(typeof window.jQuery==="undefined"){var c=document.createElement("script");c.type="text/javascript";c.src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js";document.body.appendChild(c);b()}else{a(window.jQuery)}})()