Multiple commands from system menu item in config.yaml

I'm running OctoPi 1.3.6 (Stable) on an original Pi B+

I am trying to get a menu item in config.yaml to execute multiple commands, but I am doing something wrong. I am using this code

system:
  actions:
  - action: GPIOer
    type: commands
    commands:
    - gpio -g write 17 1
    - gpio -g write 18 1
    name: GPIOer
  - action: GPIOer2
    type: commands
    commands:
    - gpio -g write 17 0
    - gpio -g write 18 0
    name: GPIOer2

But it generates the error:
Command custom:GPIOer2 does not define a command to execute, can't proceed

I've also tried:

system:
  actions:
  - action: GPIOer
    command: gpio -g write 17 1
    command: gpio -g write 18 1
    name: GPIOer
  - action: GPIOer2
    command: gpio -g write 17 0
    command: gpio -g write 18 0
    name: GPIOer2

But that ignores the second command in each case.

The relevant section around line 77 of /etc/init.d/octoprint looks like this:

       --exec $DAEMON --chuid $OCTOPRINT_USER --user $OCTOPRINT_USER --umask $UMASK -- serve $DAEMON_ARGS
       gpio export 17 out
       gpio export 18 out
       RETVAL="$?"

I know that it's something simple, but I just can't seem to work out what. Please can someone point me in the right direction, thanks.

There's no indication that more than one command is possible in that section. Just join them on the same line with a semicolon.

Brilliant. Thank you so much. This completely solved my problem.

system:
  actions:
  - action: GPIOer
    command: gpio -g write 17 1; gpio -g write 18 1
    name: GPIOer
  - action: GPIOer2
    command: gpio -g write 17 0; gpio -g write 18 0
    name: GPIOer2