Used in theme functions.php - set Elementor Library post type to use built-in Canvas template by default

single-elementor_library.php

/* ---------------------------------------------------------------------------
 * Force Elementor Library to use Canvas Template
 * - this gist file name can also be used in your theme to override the template instead of this
 * --------------------------------------------------------------------------- */
function get_elementor_library_post_type_template( $single_template ) {
     global $post;

     if ($post->post_type == 'elementor_library') {
          $single_template = WP_PLUGIN_DIR . '/elementor/includes/page-templates/canvas.php';
     }
     return $single_template;
}
add_filter( 'single_template', 'get_elementor_library_post_type_template' );