New views handler for multiple value fields - show count

Going through old issues.

Not sure if adding a field handler for this would be the way to go here, expanding the 'Multiple field settings' in \Drupal\views\Plugin\views\field\EntityField::multiple_options_form with a 'count' option might work, or people could do this in a theme since you can just run this through '#theme' => 'item_list'

But offering this option might help people avoid switching on aggregation which always brings a whole new set of problems

It would be great to have this :)

This would be great. In addition to count, it could sum, average, etc.

In the meantime, field_count_formatter → module is useful.