Fatal error: Uncaught Error: Call to undefined function vc_shortcode_custom_css_class() in /home/avantart/public_html/wp-content/plugins/xtender/vc/class.timeline.php:57 Stack trace: #0 /home/avantart/public_html/wp-includes/shortcodes.php(325): xtenderVCTimeline->timeline(Array, '[xtender_timeli...', 'xtender_timelin...') #1 [internal function]: do_shortcode_tag(Array) #2 /home/avantart/public_html/wp-includes/shortcodes.php(199): preg_replace_callback('/\\[(\\[?)(xtende...', 'do_shortcode_ta...', '[vc_row full_wi...') #3 /home/avantart/public_html/wp-includes/class-wp-hook.php(288): do_shortcode('[vc_row full_wi...') #4 /home/avantart/public_html/wp-includes/plugin.php(206): WP_Hook->apply_filters('[vc_row full_wi...', Array) #5 /home/avantart/public_html/wp-includes/post-template.php(253): apply_filters('the_content', '[vc_row full_wi...') #6 /home/avantart/public_html/wp-content/themes/astra/template-parts/content-page.php(59): the_content() #7 /home/avantart/public_html/wp-includes/template.php(724): require('/home/a in /home/avantart/public_html/wp-content/plugins/xtender/vc/class.timeline.php on line 57