Comment 8 for bug 1720890

I didn't realize there was libvulkan-dev package available I did another purge/clean install including the dev file and noticed there was extra information in vulkaninfo after..My appologies for forgetting to include one initially.
It comes down to 4 extensions not seen/available with the supplied libvulkan_radeon.so that become available once I drop in Oibaf's libvulkan_radeon.so . They are :

===============4 missing from default===========

 VK_KHR_image_format_list : extension revision 1
 VK_KHR_bind_memory2 : extension revision 1
 VK_AMD_rasterization_order : extension revision 1
 VK_KHX_multiview : extension revision 1

Hopefully the above might be helpful if a bit late