How to change default link to _self?

You can use the Custom Target attribute for each attachment, but that will probably be a lot of work for you.

You can also use some custom code:

function foogallery_override_target( $attr, $args, $foogallery_attachment ) {
	$attr['target'] = '_self';
	return $attr;
}

add_filter('foogallery_attachment_html_link_attributes', 'foogallery_override_target', 10, 3);

which you can add to your functions.php

Thanks, I’ve added that. I would think this should be a setting in FooGallery since it’s an option that’s available with no way to implement it for many users who don’t know how to add things to functions.php.

Absolutely, I agree. I have never considered this scenario before. I have added it to our backlog a future release. cheers!

Thanks! That would be a great addition.