[4.0] Custom Fields Multiple List Layout AJAX Select Missing

[David2376]

Steps to reproduce the issue

Create a custom field with type list and multiple set to yes.
Create or edit a new article.

Expected result

Expecting the list to be an AJAX select list like in Joomla 3. (see attached images)

Actual result

The list is a scrolling list. (see attached images)

System information (as much as possible)

Joomla 4.0.0-rc4

Additional comments

[David2376]

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/34941.}

[brianteeman]

Please test #36551