--- a/testing/marionette/element.js
+++ b/testing/marionette/element.js
@@ -769,17 +769,17 @@ element.toJson = function(obj, seenEls) 
 };
 
 /**
  * Check if the element is detached from the current frame as well as
  * the optional shadow root (when inside a Shadow DOM context).
  *
  * @param {nsIDOMElement} el
  *     Element to be checked.
- * @param nsIDOMWindow frame
+ * @param {nsIDOMWindow} frame
  *     Window object that contains the element or the current host
  *     of the shadow root.
  * @param {ShadowRoot=} shadowRoot
  *     An optional shadow root containing an element.
  *
  * @return {boolean}
  *     Flag indicating that the element is disconnected.
  */
@@ -905,22 +905,18 @@ element.isVisible = function(el, x = und
     return false;
   }
 
   if (el.tagName.toLowerCase() == "body") {
     return true;
   }
 
   if (!element.inViewport(el, x, y)) {
-    if (el.scrollIntoView) {
-      el.scrollIntoView({block: "start", inline: "nearest"});
-      if (!element.inViewport(el)) {
-        return false;
-      }
-    } else {
+    element.scrollIntoView(el);
+    if (!element.inViewport(el)) {
       return false;
     }
   }
   return true;
 };
 
 element.isInteractable = function(el) {
   return element.isPointerInteractable(el) ||
@@ -998,16 +994,28 @@ element.getInteractableElementTree = fun
 };
 
 // TODO(ato): Not implemented.
 // In fact, it's not defined in the spec.
 element.isKeyboardInteractable = function(el) {
   return true;
 };
 
+/**
+ * Attempts to scroll into view |el|.
+ *
+ * @param {DOMElement} el
+ *     Element to scroll into view.
+ */
+element.scrollIntoView = function(el) {
+  if (el.scrollIntoView) {
+    el.scrollIntoView({block: "end", inline: "nearest", behavior: "instant"});
+  }
+};
+
 element.isXULElement = function(el) {
   let ns = atom.getElementAttribute(el, "namespaceURI");
   return ns.indexOf("there.is.only.xul") >= 0;
 };
 
 const boolEls = {
   audio: ["autoplay", "controls", "loop", "muted"],
   button: ["autofocus", "disabled", "formnovalidate"],