1. Bring up Alfred with the hotkey
2. Type "alf", see "Show Alfred Preferences" is the default
3. Press Return key.
Result: Alfred icon eternally bounces in the dock (OK, I wanted about a minute). Only option is to force quite it by right clicking on the icon and selecting "Force Quit"
Same results if I attempt to launch it by selecting "Preferences..." from the Alfred menu. Both methods tested multiple times.
BUT...
Selecting "Check for Updates..." from the Alfred menu launches the app within a second, and navigating to the various sections and subsections works fine.
MacBook Pro 15" Touch Bar 2016, macOS 10.15.2, Alfred 4.0.8.