Question: mission control shrinks windows to nothing
Recently (not sure if it was before or after 10.13.3 upgrade) I noticed that when I wanted to move windows between spaces, the Mission Control view was blank ... almost. Here's a movie that demonstrates it. You can see that the thumbnails of the other two spaces are not blank, but the current one is.
I found a similar report from 10.8.4 (5 years ago) but there was no solution.
iMac (20-inch Late 2006), Mac OS X (10.7.5)