I'm using v0.2.17 and only manually sync my contacts from Google Contacts (I only use Gmail to update any contacts all other clients such as TB, phone, etc. only update 1 way). In Thunderbird I set the field "Allow remote content" for some of the contacts but then on the next sync that option is unset.
Is it possible to not change the values of fields in TB that do not exist in Google Contacts, for a given contact? If so, how should I configure the add-on? If not, could you please add the option in the next version?