@HHddharvey: Thanks for reporting this. For future reference, please use the bug report form (linked from the top of the task creation page) to create a bug report, and include required information (web browser and web browser version; link to reproduce; etc). I assume you're using a Chromium based browser?

I have observed this on Firefox and Chrome on desktop (the image in my original post was taken on Firefox 91.0.2 64-bit). I have also observed this on Chrome on Mobile (Android).

I also tested whether zoom affected it just now on Chrome (since that other report mentioned it). And it does. And the way that zoom levels affect characters seems to differ. For example one character was rendered correctly when fully zoomed out, incorrectly when zoomed in, and correct when zoomed even further in. Haven't tested zoom on Firefox yet. I don't know if Firefox is Chromium-based too?

If you can reproduce this with Firefox, then please provide clear and exact steps to reproduce which leave no room for interpretation for someone else, plus version and operating system info. Thanks a lot! :)

There was no way to reproduce it except for opening random pages until some symbols were sideways. If an issue was present on a particular equation on one page, then it would tend to still be present with that equation when refreshing (indicating a level of persistence) - but it sometimes randomly fixes itself after some time.

The Firefox version was given in my earlier comment.
The operating system was Windows 10 Home 64-bit (I don't have the precise build available at the moment).
I also observed this on Chrome (version 94.0.4606.85) on Android 10 (build number 00WW_1_290_SP02, kernel version 4.14.117-perf+).

I will add that I have not noticed this issue recently. I'll update if I see it again.