There are 2 personal dynamic icons next to the user avatar: The To Do icon and the Notifications Icons.
Their purpose and behavior is different as will be explained in this article.
The To Do Icon:
This icon indicates if the current user has open tasks and how many, and licking it will list them and allow the user a quick access to most urgent task and start processing them:
When clicking "Go to My Tasks", the user will be directed to a dedicated page that displays all tasks categorized by type: e.g. Pending Expert Reviews, Join Requests that need to be approved, Rate Submissions, and the state owners' Moderation tasks . It also indicates whether a task is completed or pending. The list is default by default to show only pending (i.e. Not Completed) tasks.
To learn more about how it works, you can watch this video which is included in the End User Tutorial.
The Notification Icon:
Indicate if there the current user has alerts related to your activity, such as being tagged by other users.
Once the user clicks it, the indicator will disappear, assuming the notification was noted.
The user can either open the relevant contant the notification relates to OR delete the notification: