I use -w or --welcomemessage with a filename at CLI like this:

jamulus-headless --nogui --server --directoryserver anygenre1.jamulus.io:22124 --serverinfo "Hear;California;US" -u 6 -w /root/welc.html

That shows the welc.html file contents when I connect.

But then I run jamulus-headless using systemctl, starting with this:

sudo systemctl edit --full jamulus-headless

I made this line:

ExecStart=/bin/sh -c 'exec /usr/bin/jamulus-headless --nogui --server --directoryserver anygenre1.jamulus.io:22124 --serverinfo "Hear;California;US" -u 6 -w /root/welc.html'

When I connect to that server, I see this:

Server Welcome Message: /root/welc.html

Oh no, that's the path, not the file contents. Is it possible to specify a full path here, and see the file contents? The syntax from CLI to systemctl sure looks the same to me.

(I want to call systemctl reload jamulus-headless to re-cache the welcome message from the file, to deliver hot new dynamic features crowds love, but instead, the file path is treated as a literal.)