WHAT HAPPENS:
When using Internet Explorer 11 to view the External Tool setup with 'Embedded' or "Embedded Without Blocks', only the page background loads along with quite a few Javascript Errors.
EXPECTED:
The page should load normally, as it does in other browsers. It also behaves normally in other LMS systems (Canvas).

I have written an LTI plugin. It behaves as expected in Chrome and FireFox, but when viewed in Internet Explorer 11 with the Embedded or Embedded Without Blocks option, the page does not load correctly. On inspection, a number of JavaScript errors are occurring - on further inspection the value of document.documentMode property is 8 while the javascript for the embedded page is running, and 11 afterwards/in a general console. I have verified that no specific Compatability View settings or document mode settings are present in the browser for either the moodle site or the tool provider domain. Also, neither are in trusted or Intranet site lists. The provider is sending <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" /> which should instruct the browser to use latest document mode.

I observed that unlike other LMS LTI implementations, Moodle uses an <object> tag to wrap the embedded LTI content. IE's developer tools do not properly expand the contents of this tag, and that leads me to suspect that this may be the culprit.