Just a PSA.
I noticed the other day that my system tray icons went all screwy and/or disappeared. Only the ones on the right hand side of the taskbar. Took a bit of figuring it out but it seems the addition of 'news and interests' into the taskbar is the culprit. The solution so far is to enable 'news and interests' (right-click on taskbar) and then disable it. Since I did that the problem has gone away (but I haven't restarted the PC either).
Just thought I'd mention it in case anyone else has noticed the problem in the last few days.
No issues with my desktop or lappy with 21H1 or any of the updates including last night's updates.