Update intune-management-extension.md

Author: Becky-Intune

memdocs/intune/apps/intune-management-extension.md

@@ -129,6 +129,8 @@ The Intune management extension has the following prerequisites. Once the prereq
 
 - The Intune management extension agent checks with Intune once every hour and after every reboot for any new scripts or changes. After you assign the policy to the Azure AD groups, the PowerShell script runs, and the run results are reported. Once the script executes, it doesn't execute again unless there's a change in the script or policy. If the script fails, the Intune management extension agent will attempt to retry the script three times for the next 3 consecutive Intune management extension agent check-ins.
 
+- For shared devices, the PowerShell script will run for every new user that signs in.
+
 ### Failure to run script example
 8 AM
   -  Check in