Clicking link with target="_blank" in IE Mode loses session data in original tab

The problem occurs with the current Edge version 80.0.361.57 (64-bit), but I've also confirmed it is still happening in the latest beta/dev/canary versions as well.  We are using IE mode within the Edge browser, and are rendering all pages in IE11 compatibility mode.

When left-clicking any link containing a "target="_blank"" attribute in an IE mode-enabled page within our intranet, the destination is successfully opened in a new tab.  However, the state of my original tab (as well as the new tab) is effectively logged out and back in, and my session is reset.  I have a new ASP and ASP.NET session ID, and all of my session variables are lost.

In contrast, if I remove the target="_blank" from the link and do a Ctrl+Left click to open in a new tab, maintaining the session is fine in both tabs.  I can also use Javascript to get around this problem, using something like onclick="return ! window.open(this.href);" to open in a new tab yet keep my session in tact.

Is this a known issue, and if so, is there a fix in the works?