Pseudo hit testing is disabled in IE11 edge mode
In Internet Explorer 10 and earlier versions, mouse clicks and touch interactions were conditionally allowed through transparent backgrounds. This feature, known as pseudo-hit testing, was seen as inconsistent because it varied on the content behind the transparent layer and it wasn't used for direction manipulation actions (such as pan or zoom). In certain cases, user interface elements wouldn't activate when touched or clicked because the event would be passed through the transparent background to other elements.
To provide better compatibility with other browsers and a more consistent experience for all interaction events (including touch and zoom), pseudo hit testing is disabled in IE11 edge mode.
Affected content won't to respond to user interaction and appears obscured when selected using the DOM Explorer or Microsoft Visual Studio.
If you run into an issue because of this change, consider reworking the page to use pointer events. Alternatively, changing the change the z-index of the target element (or the size of the size of the transparent layer) may resolve the issue.