I have this exact issue, the problem can be fixed by opening the contents of the app and opening the "MacOS" folder you will find an executable, if all you see is the executable being a blank page then follow a tutorial to make the file an executable
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make sure you're in the right folder
you can do this by right-clicking on the application in Finder and "show package contents"
then navigate to Contents -> MacOS and you'll find the executable
now type "chmod +x " in terminal (don't enter it yet), and drag and drop the executable from Finder to the terminal
after that it should work