Since multiple selects are kind of the basis of this module, it would be good for performance to cache the output of _multiple_selects_get_options(), since that's always the same list (per field instance!).
If #1503480: Remove already selected options from the drop-down menus (so to prevent them from being allowed more than once) → is applied, this won't work, because all select lists will be different => no caching possible. If it's enabled with a checkbox, it would still be possible though.
Closed: won't fix
1.0
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