Add the "As an element index" view mode to relational fields.

[mjniland1]

The Matrix field includes the very useful option to set the view mode to "As an element index." Our content authors make regular use of this feature, but one of them recently asked if the same option could be added to an Asset field that often contains 50+ related assets.

Would it be possible to extend the element index view mode to all relational fields (Entries, Assets, Tags, etc.)? This would allow users to quickly search, filter, and order related data when a field contains a significant number of elements.

I understand that we could use a Matrix field in place of the Asset field, but this would prevent users from being able to “select all” within a folder when creating a relation.