Nouveau - May 2017 - Known bug? Two adjacent letters randomly not rendered or painted over

Hi, folks. Using the Noveau drivers on my RHEL7 Thinkpad (which is how our IS
shop supplies these machines), I will see it drop two letters out of a window
full of text (as if rendering them in the background color or drawing a
rectangle  of that color over them).

 This happens in everything from Eclipse mouse-over syntax pop-up windows to
Libre Office word processing screens. I haven't found​ and pattern yet in
what gets stepped on or when.

I have occasionally been able to get it to paint just the bottom few pixels of
these characters, but I can't provoke that reliably yet.

I have seen some archived discussion of a similar effect, so this may be a
Solved Problem. If so please let me know and point me to upgrade process. If
not, I'm willing to do some additional data gathering if anyone can suggest
useful experiments.

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OMG GOP WTF ?!?