I have explicitly told my board I am not dealing with IE issues any more and that my response to IE issues is to recommend using a current Chromium-based browser (e.g. Chrome, new Edge) or Firefox. And I am pretty sure that was based on someone from XF posting that they weren't supporting IE any more, or a least not going out of their way to do so.
Mostly this but certainly we're heading fast towards little to no support for it. We'll call it "best effort".
We will at least look to see if we can improve things here but on the whole whether we sort this or not the best and most emphatic advice I can give is: start using Chromium Edge or an alternative browser.
All users using IE11 and very old versions of Edge get a browser warning on every page:
It's just a sub-standard experience overall and in some cases it is blocking us from implementing newer code standards so it's to everyone's benefit to urge their users to change their browser.
As noted, IE is only minimally supported at this point (and it's very likely that its support will be dropped entirely in the next significant release). However, I have made some changes here that will somewhat improve the fallback of the article preview system (and a couple other places) in browsers that either lack grid support or have some bugs (which have generally been resolved in more recent releases).