It is very annoying when we get WordPress Plugin or Theme Update notifications. And the notification won’t go until we don’t update to the latest version. Updating the WordPress Core or Plugin Theme will affect the custom code that is used at the time of developing the website. Below is the code which helps you to disable update notifications.
Go to Appearance > Theme Editor > Select Theme Function (functions.php) > Insert the below code > Click Update File
function remove_core_updates(){ global $wp_version;return(object) array('last_checked'=> time(),'version_checked'=> $wp_version,); } add_filter('pre_site_transient_update_core','remove_core_updates'); // Disable WordPress Update Notification add_filter('pre_site_transient_update_plugins','remove_core_updates'); // Disable Plugins Update Notification add_filter('pre_site_transient_update_themes','remove_core_updates'); // Disable Themes Update Notification