An application's icon will bounce in the macOS Dock until the application enters its main event loop and begins responding to user input.
See How do I make the dock icon stop bouncing after my app wrapper script starts?
what does an app do to satisfy the dock bounce?
An application's icon will bounce in the macOS Dock until the application enters its main event loop and begins responding to user input.
See How do I make the dock icon stop bouncing after my app wrapper script starts?