Yeah, something has gone screwy on IE -- the headings inside the forums all seem to be set in bold and the navigation bar (Main, SimMatchup, SimLeague, Dynasty, Forums and the Sitemail icon) all disappear when you're in one of the forum threads and you have to click on the Wif Sports logo to get back to Home.
I've been using Microsoft Edge after upgrading to Windows 10 for a few months with no problem, and FireFox still works fine.