Twenty Fourteen: Non-Responsive Sub-Menus on iPad Pro in Horizontal View

[katinthehatsite]

It seems that the sub-menu items are not responsive and do not work on some devices such as iPad Pro in the theme Twenty Fourteen when the device is in the horizontal view.

The steps to reproduce:

• activate the theme Twenty Fourteen;
• create a menu with sub-menu items in the Appearance - Customize;
• select the display location for the menu to be "Top Primary Menu";
• save and publish your settings;
• go to your site on iPad Pro and try clicking on the menu to make a sub-menu appear in the
• horizontal view.

What I expected:

the sub-menu items to appear

What happened:

the sub-menus did not appear and were not responsive

Further details:

I tested on iPad Pro and iPad 4; the issue seems to be happening on iPad Pro specifically - I suspect because it has a desktop view in the horizontal position where you can see all of the items.

On iPad 4, the menu is a hamburger menu, and once you click to open it, all menu items are visible.