Another thing I miss, is the possibility to store addresses directly on a different location, e.g a cloud. This in order to synchronize with other computers. Synchronizing with other local computers does not function now. The files get corrupted, probably because the prefs.js file also needs to be synchronized at the same time. But this again causes problems with other add-ons. Maybe cardbook needs an own prefs.js file.
This review is for a previous version of the add-on (33.4).
This user has 2 previous reviews of this add-on.