When JAWS is running, a full-screen black and empty window is present. This can occur particularly when publishing JAWS as an application in Citrix.
Add the following parameter to the jfw.exe shortcut:
-DisableOverlay
C:\Program Files\Freedom Scientific\JAWS\2022\jfw.exe -DisableOverlay
If using a Citrix Published App, this should be done on the path to run the published JAWS on the Citrix server.