Feature request: Make long_slow_command | less +&foobar\n usable

[paddor]

I'd like to use less like long_slow_command | grep foobar. That way it would filter lines right after start up, but I could still switch to viewing all lines later (using &\n). This is useful e.g. in web development where you have a Procfile that starts multiple commands like backend, frontend, and verbose simulators, and only want to see certain lines of the simulators by default.

Compare the following two commands:

tail -n +1 -f /etc/hosts | grep 127
127.0.0.1 localhost
127.0.1.1 my-machine-name
^C

tail -n +1 -f /etc/hosts | less +\&127\n  # Fish syntax

The second command shows nothing until you hit ^C and then shows all lines.

I'm not aware of any currently supported less options to get this behavior. Using stdbuf -i0 -o0 doesn't help.
Thanks.