Multiselect Configuration
Multiselect has one setting, “Multiselect Options”, a textarea in which you specify each option you want as part of the multi-select.
List one option per line:
Herbie Hancock
Miles Davis
The BeatlesYou can optionally specify input values for each option, and organize
options into optgroup\ s:
Jazz
    herbie : Herbie Hancock
    miles : Miles Davis
Rock
    beatles : The Beatles
    bobby : Bob Dylan