Answer
IEE's embedded web-browser functionality is built on the older Internet Explorer rendering engine internally, regardless of which browser is actually configured as the Windows default — so a URL that would behave differently or fail specifically under classic Internet Explorer's rendering behaves the same way inside IEE, even if IE itself hasn't been the system default browser in years. If a specific URL/page is known to have issues in Internet Explorer specifically but works fine in Chrome or Edge, expect that same broken behavior to show up when it's opened from inside IEE, since IEE's embedded view uses IE's engine rather than whatever browser is set as the OS default.