You can go into settings, and rotate apply rotate apply, and they spring back to life.
Oof, even though there was no kernel update, still needed to rebuild nv driver, that was the real cause.
I’m using dual monitors with the 396.24 driver installed the hard way, and see no similar problems after a zypper dup to snapshot 20180804 with the 4.17.12-1 kernel. Good luck troubleshooting.
Just had to rebuild nv driver! After I rotated and enabled the 2 dead screens, I noticed performance was really bad, which is when I realized what happened. I guess something related to x.org was updated.