I can confirm that this is happening only in combination with Display Link drivers.
Yesterday everything was working fine on Ubuntu 18.04 with Nvidia drivers, but today I've installed DisplayLink 5.1 so that I can use 2 external monitors at work and then square appeared.
I can confirm that this is happening only in combination with Display Link drivers.
Yesterday everything was working fine on Ubuntu 18.04 with Nvidia drivers, but today I've installed DisplayLink 5.1 so that I can use 2 external monitors at work and then square appeared.