Rated 3 out of 5 stars

Bewertung eigentlich noch nicht möglich, aber da es keine andere Möglichkeit der Kontaktaufnahme gibt hier eine Frage: How to import the already existants Thunderbird adresses into Cardbook?

This review is for a previous version of the add-on (7.4). 

you may contact me here : cardbook.thunderbird(at)gmail.com

for your problem, there is no easy way... when Cardbook will be more mature, I'll write something for this but not for the next 6 months...

Edit : somebody told me this path :
There's a way:
1/ Export your existing contacts as vcf (e.g. with
MoreFunctionsForAddressBook
https://freeshell.de/~kaosmos/morecols-en.html)
2/ open the file generated and then change all these strings "VERSION=2.1" with this string "VERSION=3.0", save it
3/ import it with cardbook

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