Question about alert

Hello,

I have a question about the alert message.

I work on the session expiration for application and I create an alert(warned) for inactivity.
The criteria for alert is 2.2.1
The user is warned before time expires and given at least 20 seconds to extend the time limit with a simple action (for example, "press the space bar"), and the user is allowed to extend the time limit at least ten times;

It is an alert, because I don’t want to change the workflow of tabulation.

In your page “https://www.w3.org/WAI/ARIA/apg/patterns/alert/”, I read :
It is also important to avoid designing alerts that disappear automatically.. An alert that disappears too quickly can lead to failure to meet WCAG 2.0 success criterion 2.2.3<https://www.w3.org/TR/UNDERSTANDING-WCAG20/time-limits-no-exceptions.html>.

Or in my case, if you move the mouse … People are active so it have to disapper.

Can this be an exception ?

Arnaud Delaloy

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