Tooltip embedded in button not working in IE 11

[tcrite]

Bug description:

Hi, it seems the tooltip is not working when embedded inside an element that is embeded in a button element in IE11, eg.

Test

This works fine in Chrome, Edge, and FF.

Link to minimally-working plunker that reproduces the issue:

https://plnkr.co/edit/Zkt147OC0OiqWh24h5Yb?p=preview

Version of Angular, UIBS, and Bootstrap

Angular: 1.5

UIBS: 2.3.1

Bootstrap: 3.3.7

Thanks for any help.

[tcrite]

Haven't figured out a solution yet, but it appears to be the mouseenter trigger not working if the tooltip is inside the button.

[tcrite]

Got around this issue by using the tooltip-is-open attribute and setting tooltip-trigger to none