All our testers can reproduce that issue. To make my life easier while I develop the app, I created a shortcut to launch it using those instructions.
Sure enough, same issue, I need to click it twice for it to work.
The first time I click it I get the Overwolf splashscreen with the progress bar that’s relatively slow. I need to wait for the progress bar to complete. Then I can click my shortcut again it gives me the splashscreen again but this time the progress bar is super fast and it starts the app instantly.
Our app is using a C# plug-in and some online JS resources too, maybe that could be relevant.