IE11: SVG icons should not be focusable

[compulim]

Screenshots

After pressing SHIFT TAB once, document.activeElement indicates it is focusing on the <svg>.

Put this line in the console to dump the current focus:

setInterval(function () { console.log(document.activeElement); }, 1000);

Version

4.13.0

Describe the bug

In IE11, press SHIFT TAB from the send box will focus on the <svg>, instead of the <button>.

Steps to reproduce

1. Launch Internet Explorer 11
2. Go to https://compulim.github.io/webchat-loader/
3. Press SHIFT TAB, note the focus is on the icon of the upload button
4. Press SHIFT TAB again, note the focus is on the upload button
5. Press SHIFT TAB again, it is now on the transcript

Expected behavior

It should not focus on step 3.

Additional context

[Bug]