When I open the index.html file in my browser, I usually see the full fidelity
version of my website, i.e., it looks just like the online version. But now
when I open it, all I see is the text only version of the webpage. I've tried
it in Chrome, Edge, and IE. This is even the case for older mirrors that I
have viewed no problem in the past. And no, there's nothing in the
hts-log.txt. 

Is there a browser setting or something that I need to change? 

Or is it possible that my IT department has blocked this somehow (they're
annoyingly strict about their firewalls, malware/virus blockers, and blocking
social media sites...)?
Thanks