Same here on my rig, it's some display bug and a distraction if you do any flying above ~15k. I hope it quickly gets fixed, one of those anoying ugly bugs that doesn't break anyhting, just looks bad (and slightly annoying/highly-noticable because it wasn't an issue before).
I ahve some SS at home I can add if needed. It apears the transparency through the text blocking in combination with the ~15k cloud layer deck in the imediate background is where the problem is at.
Edit: NM, saw there was a patch for it today.