Wikimore

This feature was removed completely in version 1.41.0.

Ajax: $wgAjaxUploadDestCheck
Enable Ajax check for file overwrite, pre-upload.
Introduced in version:	1.11.0
Deprecated in version:	1.38.0 (Gerrit change 722358; git #6c4ac7dd)
Removed in version:	1.41.0 (Gerrit change 949596; git #ee4472fe)
Allowed values:	(boolean)
Default value:	`true`
Other settings: Alphabetical \| By function

Details

Enable Ajax check for file overwrite, pre-upload.

This is not related to the deprecated action=ajax ($wgAjaxExportList) functionality.