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I log in... and am logged in at JS. Then i click on a link in the time-line or on the notification icons and i get the loggin module from Joomla again...
Its then when i am log in again i see the frontpage again from JS and then i can click on links and the notification icons and it works...
that cache issue. please try with www and non-www. if happening at both, please turn off OPcache at your server.
you can asking server support to do it.