Fatal error: Uncaught Error: Call to undefined function is_main_site() in /home/tcentral7788/public_html/lincoln.testcentral.com.au/wp-includes/update.php:1152
Stack trace:
#0 {main}
thrown in /home/tcentral7788/public_html/lincoln.testcentral.com.au/wp-includes/update.php on line 1152