-**Prepend when not full yet**: If the field allows multiple values, the given value will be inserted as the first item, if the max. cardinality is not reached yet. Otherwise, this action will be skipped.
-**Prepend and drop first when full**: Same as above, but if the max cardinality has been reached, the first value will be removed and the new value inserted at the beginning to the list.
-**Prepend and drop last when full**: Same as above, but instead of dropping the first, this will drop the last item before inserting the new value at the beginning of the list.
-**Remove value instead of adding it**: Remove the value from a multi-value field, if it's caontained in the list of existing items.
-**Remove value instead of adding it**: Remove the value from a field, if it's contained in the list of existing items. If this removes the last remaining value of the field, then the field will be empty (for an example of this, see [this issue](https://www.drupal.org/project/eca/issues/3504388)).
