Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function "bones_gallery_style" not found or invalid function name in /usr/www/users/katharnd/src/wp-includes/class-wp-hook.php:324 Stack trace: #0 /usr/www/users/katharnd/src/wp-includes/plugin.php(205): WP_Hook->apply_filters() #1 /usr/www/users/katharnd/src/wp-includes/media.php(2755): apply_filters() #2 /usr/www/users/katharnd/src/wp-includes/shortcodes.php(434): gallery_shortcode() #3 [internal function]: do_shortcode_tag() #4 /usr/www/users/katharnd/src/wp-includes/shortcodes.php(273): preg_replace_callback() #5 /usr/www/users/katharnd/src/wp-includes/class-wp-hook.php(324): do_shortcode() #6 /usr/www/users/katharnd/src/wp-includes/plugin.php(205): WP_Hook->apply_filters() #7 /usr/www/users/katharnd/src/wp-includes/post-template.php(256): apply_filters() #8 /usr/www/users/katharnd/src/wp-content/themes/katharinabintz/page.php(10): the_content() #9 /usr/www/users/katharnd/src/wp-includes/template-loader.php(106): include('/usr/www/users/...') #10 /usr/www/users/katharnd/src/wp-blog-header.php(19): require_once('/usr/www/users/...') #11 /usr/www/users/katharnd/src/index.php(17): require('/usr/www/users/...') #12 {main} thrown in /usr/www/users/katharnd/src/wp-includes/class-wp-hook.php on line 324