Hello, guys, i`m somehow having the exact same problem. i did recently start using a second monitor, so i suspect it might have something to do with that, but the windows do not appear there either.
any ideas what else might be causing this or how i could troubleshoot?
EDIT: nvm, i fixed it.
Apparently if the second monitor is powered off but the monitor setting is set to "extend", the windows just blip out of existence.