i´ve just installed a fresh Magento2 on my webspace to prepare the migration of my Magento 1.9.
I installed my theme (Infortis) and created my products and did the first test-salse. Everything fine...
But if I try to logout as a Customer this error appears:
There has been an error processing your request
Notice: Undefined index: form_key in vendor/magento/module-customer/Model/Plugin/CustomerFlushFormKey.php on line 48
Since there isn't even a valid google result on this file, I hope that you can tell me what to do.