annlickander

add_filter( 'facetwp_facet_render_args', 'your_function_name' );

// General example
function your_function_name( $args ){
  if ( 'name_of_facet_wp_filter' == $args['facet']['name'] ) {
    foreach ( $args['values'] AS $key => $value ) {
      // insert logic for changing the label / display value
      $args['values'][$key]['facet_display_value'] = 'label name';
    }
  }

annlickander

<?php
/* Change filename and extension to lowercase */
add_action('add_attachment', 'hip_rename_attachment');
function hip_rename_attachment( $post_ID ){

    $post = get_post( $post_ID );
    $file = get_attached_file( $post_ID );
    $path = pathinfo( $file );

    $newfile = $path['dirname']."/".strtolower( $path['filename'] ).'.'.strtolower( $path['extension'] );