As I couldn't find my issue here, I have to assume currently that it's something on my end, but maybe I might not be alone?

See screenshots, the game output is cut off.

First time I noticed that was on May 8th (screenshot with aqua lines), but it might have existed already prior, since I didn't log into MC for a while (however, I faintly recall it existed already a bit earlier, but thought it was some sort of placeholder for future advertisement or other notes by Mojang or Microsoft, similar to the Launcher which was changed like that not so extremely long ago).

It still happens for me, and I don't know if it's potentially my anti-virus program, which is why I mention it.

Note how also the first tables' text appear black, not white like the game output itself, which is clearly different from my experience before.