The configuration information on the alert tab in Edge Version 93.0.961.52 for Grafana version 7.5.7. First attached screenshot shows the issue. I cleared cookies/cache, no help. I rebooted my computer and I was able to see it again. I resized the configuration section of the panel to be able to take a screenshot (attached). Shortly after that the problem returned.
I was able to fix the issue. By rolling over the alert tab
The resizing pointer showed up and I was able to pull it down. The issue here is that when I first resized that it was resized to the whole panel, but when I went out and back in the resizing had expanded to the whole panel and it became blank.