I'd like to be able to upload PPT files in the CP, but I'm getting the "File not allowed" error. Can anyone tell me how to resolve this? This is in EE5 5.3.0--all the solutions I've seen have been in the EE2 format.
I've tried adding this to mimes.php with no success:
$config['mime_whitelist_additions'] = array( 'application/vnd.ms-powerpoint' );
Then I refresh the CP and try again, getting the same error.