This is a basic JavaScript file that is used to control MIDI inputs to the MaizeDMX application.
The Documentation for how to get the MIDI section working is literally:
Do you have a MIDI controller with fader and buttons? If so, great! You can support it by writing some javascript :)
In the controllers section of the settings tab, you can add any number of controller and
write or paste the supporting javascript in the code editor below.
Which is not helpful, there was an example provided in the doc, but it also wasn't super helpful.
So I wrote a basic script that allows for inputs from another application to go to the next cue in MaizeDMX.