The dependency in the 5.2 ebuild is || ( app-misc/screen app-misc/tmux ) but: # byobu /usr/bin/byobu: line 155: exec: tmux: not found Of course byobu supports both and one can explicitly select a multiplexer by running byobu-{tmux,screen}, the default being tmux. This can be confusing for users. Maybe screen and tmux should be USE-flags or the installed "byobu" script be a link to whatever multiplexer really is installed. Reproducible: Always
While I think this would be better handled with some better error handling upstream I've added a screen use flag to 5.15 that sets the default backend to screen if it's enabled and updated the deps to match.
