Support Webp Image

function webp_upload_mimes( $existing_mimes ) {
    // add webp to the list of mime types
    $existing_mimes['webp'] = 'image/webp';

    // return the array back to the function with our added mime type
    return $existing_mimes;
}
add_filter( 'mime_types', 'webp_upload_mimes' );