It looks like a limitation of SPFx's feature framework's that you can't associate field customizer to existing OOTB fields.
Reference - Highlighting which page is the welcome page in a site
Having said that, you can associate Field Customizer extension to existing OOTB list columns or site columns by setting ClientSideComponentId property of column with ...
Yes that's possible. We will need to hide the column value from a system view. Also stop the same user(user group) from customizing the views, to make sure he isn't able to add the column in other views.
Se in the above image you can change the column value with *** for a specific user group.
More details here: field customizer spfx
Check out the below options:
You can use PowerApps to customize the SharePoint online List forms.
Check below article for more information:
Customize a SharePoint list form by using PowerApps.
You can also use InfoPath(Microsoft will support InfoPath upto 2026) to customize the list forms.
You can also build the fully customized forms using SharePoint ...
No not at the moment. Currently Field Customizers are only to display data in list view (non edit mode).
But see user voice entry Field Customizer Evolution: Forms, Quick Edit Mode
(and maybe upvote it)
Currently, we cannot edit the modern list view page and insert code to modify OOB options.
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