SNAP freeze seconds after it is opened

[marpet]

Does your Linux run in a Virtual Machine? It might help if you enable 3D graphics support., if possible.
Sometimes the world wind module generates some trouble.
Have a look here:

SNAP 5.0 fails to launch on Linux

This happens probably due to the limited 3D capabilities of the VMs. You can either increase the 3D capabilities by changing the VM configuration or you remove the world-wind jar from the installation. Delete snap/modules/org-esa-snap-snap-worldwind.jar from the installation directory. If you then start SNAP you get a warning that this module is missing. Accept it and let SNAP remember the decision.