This is a good one but when (for example) I'm connected to my account here https://addons.mozilla.org/fr/firefox/addon/ and use the add-on then reloading the page I'm still logged in. Is it normal? Does it not supposed by clearing all the stuffs take me logged off?

EDIT: I was using the private browsing mode. I test the same manipulation with private browsing turned off and it works. Surely a limitation in the way cookies are managed in private browsing mode.