Have a look around in your settings.
In settings you may be able to prevent that from happening if the extensions and etc. are all set to some default setting.
This article has a few suggestions and shows where extensions are stored.
I am running Ubuntu Gnome 13.10 with Gnome 3.10. My problem is that every time I reboot the OS all the shell extensions are turned off. The weird thing is that their settings are kept. They are just
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