Well, without making a direct change to the plugin files it's not possible. I will try to detail a possible change for you.
1. You will have to add an extra line to one of the core plugin files. I will make sure to add this line to the next release as well, so an update won't break it. Open up the wp-content\plugins\related-posts-pro\includes\related_content.class.php file and scroll to line 82, which should be this:
$args = wp_parse_args($args, $default_args);
2. Just under that line, place this:
$args = apply_filters('rpp_args', $args);
3. Then instead of the code I suggested earlier, use this one to exclude by IDs:
The only difference that in this case the IDs are simply listed as a string, not an array.
Let's hope this works 🙂
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