bbpress doesn’t load the the necessary scripts (reply.js etc) when embedding a topic as a shortcode. This is because of the conditional checks on line 158 of bbpress-functions.php

if ( bbp_use_wp_editor() && is_bbpress() ) {

[@robin-w Moderator 4 years, 6 months ago]

you could just enqueue it

bbp_enqueue_script( bbpress-editor-always, 'js/editor.js', array( 'jquery' ), '2.6.4', true );