This happens on a regular basis, and I don’t know how or why this happens.
The buttons still work, and they still show information when you hover over them:
System Information:
CPU: Intel(R) Core™ i5-8250U CPU @ 1.60GHz
Memory: 8.0 GB
GPU: Intel(R) UHD Graphics 620
Expected behavior
I expect the buttons to show up normally, not covered with random gray boxes.