Adding the following code snippet to my child theme’s functions.php file worked for me

function bbp_enable_visual_editor( $args = array() ) {
    $args['tinymce'] = true;
    return $args;
}
add_filter( 'bbp_after_get_the_content_parse_args', 'bbp_enable_visual_editor' );

I obtained this solution at the following url:

https://codex.bbpress.org/enable-visual-editor/