14.3 Mail.app - Corrupted/Garbled Text When Composing Messages

After updating to 14.3, I've noticed Mail.app messages (replies or new) will begin garbling and corrupting text display while you're writing (similar to writing in this field here). Usually when you've written a few paragraphs, the prior (or even current) text will garble with previous content, moving it around, erasing some, or even overlaying it with a previous paragraph.

Importantly, the text itself is not changed, as can be seen if you just ignore it and keep typing. However, if you stop and try to select the text, it cannot be grabbed, since it's not really there. It is a visual corruption only, but when you don't know what you have written, it's hard to confirm what's, well, written.

I've restarted, as well as reinstalled the OS with no change.

This is while Mail is in fullscreen and the message is using split-screen.

There clearly seems to be a text display bug (graphics or WebKit perhaps), but I'm trying to determine if it's just me or others are noticing it as well. I will also file a bug (Feedback Assistant) on the issue.