Entity reference form

Content edit form with single and multiple value entity reference fields, rendered with each of the reference widgets: autocomplete, autocomplete with tagging, select list, check boxes/radio buttons, and the simple and complex inline entity forms. The values are dummy ones, so the page renders the same on every site.

Single value

Cardinality 1, "Autocomplete" widget: a single textfield, filled with the label and the id of the referenced entity.
Cardinality 1, "Select list" widget: the empty option is the one the field system prepends to an optional field.
Reviewer
Cardinality 1, "Check boxes/radio buttons" widget.

Multiple values

Unlimited cardinality, "Autocomplete (Tags style)" widget: one textfield holding every value, separated by commas.

Contributors

 Order
Unlimited cardinality, "Autocomplete" widget: a table of widgets, ordered by drag and drop, with a button per row to remove it and a button below to append one.

Approvers

 Order
Cardinality 3, "Autocomplete" widget: every row is rendered up front, so the table has no button to add or to remove one.
Unlimited cardinality, "Select list" widget: a multiple select, with no empty option.
Subscribers
Unlimited cardinality, "Check boxes/radio buttons" widget.