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The ['interface'] section contains configuration for display and listing in various parts of the backend. Extension authors often ignore these settings and a lot of extensions in the wild don't use that array part.
This is how the "pages" table is configured for these settings:
'interface' => [ 'showRecordFieldList' => 'doktype,title,alias,...,backend_layout,backend_layout_next_level', 'maxDBListItems' => 30, 'maxSingleDBListItems' => 50 ],
Max number of items shown in the List module. Defaults to 20 if not specified.
Maximum number of items shown in the List module, if this table is listed in extended mode (listing only a single table). Defaults to 100 if not specified.
string (list of field names)
Defines which fields are shown in the show-item "info" dialog. For example 'doktype,title,alias,hidden,...'. To see that dialog go to the list module in the backend and click on the icon of a record in the right pane. Then choose 'info' in the popup menu.
If not specified, the info dialog shows only a couple of default fields, it is good practice to at least add a list of main record information fields here.