Hello,
I’m seeing this when plugging in a PS4 controller via USB on a macOS Catalina device.
The SDL_DarwinJoystickDriver spots it and adds it, then the SDL_HIDAPI_JoystickDriver spots it and also adds it, and I end up with one pad being reported as two and all button presses duplicated.
I’m not sure if it’s a bug, or if it’s my mistake and I should only be using one driver.