Alert Summary: -
If current user has ManageWeb permissions, we'll consider them an administrator. Otherwise, we'll consider them a viewer.
So Administrator can add alert, edit alert and delete alert items.
Viewer can only view the alert items which are created by an administrator. It has been categorized in three ways, I) critical, ii) warning, iii) information.
Note: Alert Items will be displayed based on Start Date and End Date , If Start Date <= Current Date && Current Date <= new End Date the condition is satisfied then display the alerts.