don't see checkbox

Based on code selective_better_exposed_filters/src/Plugin/better_exposed_filters/filter/SelectiveFilterBase.php line 42

if ($filter->isExposed() && (
      $filter instanceof TaxonomyIndexTid
      || $filter instanceof EntityReference
      || $filter instanceof SearchApiOptions
      || $filter instanceof Bundle
      || $filter instanceof VERF
      || $filter instanceof ListField
      ) && !($filter instanceof TaxonomyIndexTidDepth)
    ) {

This means that the `Show only used items` will appear when the filter is exposed, and its source is an EntityReference, SearchApiOptions and etc.

ah thanks @ambot112! i guess this won't work for me then...bummer.

i don't see a way i can close this issue so if someone with that privilege can close it for me, thanks!