Hi Marc Roussel,
Thank you for contacting us!
I just checked remember me functionality and seems to work just fine!
Basically it works like this: if you are logged in and checked Remember me, you will be logged in the same browser for 7 days.
Nevertheless if you logout from our site you won't be remembered anymore!
Can you tell us what is your scenario in order to verify is it expected or there is an issue?
the Telerik team
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