My Program Will Not Open On Mac, But Program Menu Is Visible

If you find that your Topaz Lab program is not opening, but the program's menu shows up in the top menu bar, you are experiencing a "full screen" error that was prevalent in MacOS 10.13 High Sierra, and is occasionally seen in newer versions of MacOS as well, such as Catalina and Big Sur.

The most common solution for this behavior is to delete your plist files:

How To Delete Your Plist Files

Once the plist files are deleted, restart the program. If it doesn't restart as expected, there may be another conflict that needs troubleshooting.