Hi,

First, thanks for this great software !

I think you could improve user experience concerning automatically collected emails, and here is how I see it :
  - Automatic contacts extension should be activated by default.
  - It should record email addresses in a specific and dedicated address book, for example "Automatically collected" or "Automatic contacts" (see also https://bugzilla.gnome.org/show_bug.cgi?id=503991).

I suggest this because I think 99% users like the email address auto-completion feature, so :
  - I think it is "fastidious" for them to search on the Internet or in the offline help how to do it, then going enable the plugin, and finally configure the plugin.
  - I think that most people wants automatically collected addresses to be separated from manually recorded contacts : they don't want to mix friends, familly, or business contacts with "one-time" contacts.
  - If they want / need to use a complete address book for personnal or business use, they will just need to go in this "Automatically connected" address book to take the contacts they want.

In my opinion, activate this extension is the most important, record addresses in a separated address book is secondary.

Thanks very much for reading,
Yvan