1] AMD GPU Pro solution
Firstly, I try to install AMD GPU Pro driver on Ubuntu 18.04 to see if this bug is fixing.
During the compilation of this driver I get an error because I have not a good kernel version.
On Ubuntu only Mesa and Nvidia drivers are in configuration management .
Under Ubuntu, for AMD GPU pro, it is not a good idea to install AMD GPU pro drivers 
2] AMDVLK
AMDVLK installation on Ubuntu is different than AMD GPU pro.
It’s a simple .deb package : Releases · GPUOpen-Drivers/AMDVLK · GitHub
The install instruction is the next :
sudo dpkg -r amdvlk /* If old version is installed on the machine, remove it first */
sudo dpkg -i amdvlk_x.x.x_amd64.deb
sudo apt-get -f install
https://github.com/GPUOpen-Drivers/A…e-built-driver
For the moment I don’t try this.
3] Mesa + RADV
This solution don’t work for UE4 Editor (see my last post)
sudo apt-get install libvulkan1 mesa-vulkan-drivers vulkan-utils
https://linuxconfig.org/install-and-…ulkan-on-linux
Conclusion
I try to see with Mesa RADV community if that’s possible to fix this pb because I would like to keept my OS with basic configuration.
I hope Epic will fix this bug…
Has anyone tested the 2nd (AMDVLK) solution on Ubuntu ?