I’m no expert, but I believe I may have succeeded in doing just that last night.
In the generator.php file, I added this:
protected function substitute_thumbnail( $post ) {
return the_post_thumbnail( array(65,65) );
}
right after the end of the
function substitute_category( $post )
function.
THEN, in the core.php file, I added “%thumbnail%” to the list of shortcodes, as such:
static function get_available_tags() {
return array(
'%post_link%',
'%date%',
'%excerpt%',
'%author_link%', '%author%',
'%comment_count%',
'%category_link%', '%category%', '%thumbnail%',
);
}
Be sure to back up and save. I did it wrong the first time and had to manually delete the plugin and reinstall it before I could get back into wordpress. But the second time, it worked like a charm.
But I’ve NEVER done anything like this before. I don’t know code. I simply guessed (based on patterns I saw in the code), and was flabbergasted and did a little dance when it worked. YAY!