portage-ng --merge
>>> Emerging : portage://x11-apps/mesa-progs-9.0.0:run?{[]}
These are the packages that would be merged, in order:
Calculating dependencies... done!
└─step 1─┤ download portage://x11-apps/mesa-progs-9.0.0
│ └─ file ─┤ 14.15 Mb mesa-demos-9.0.0.tar.xz
└─step 2─┤ install portage://x11-apps/mesa-progs-9.0.0
│ └─ conf ─┤ USE = "X* -gles2 -vulkan -wayland"
└─step 3─┤ run portage://x11-apps/mesa-progs-9.0.0
Total: 3 actions (1 download, 1 install, 1 run), grouped into 3 steps.
14.15 Mb to be downloaded.