SUMMARY Data is lost when exporting internal contracts as VCard. The internal .vcf file managed by Akonadi for a specific contract contains a 'categories' field that includes some information about the placed tags for a specific contract. The exported VCard file (tested with either VCard 3.0 or 4.0) does not contain that or any related fields. STEPS TO REPRODUCE 1. Make an arbitrary contact and assign tags to it within the application 2. Observe that the internal .vcf file indeed contains information about the tags 3. Export the contact as a VCard 4.0 (works 3.0 too, haven't tested the rest) OBSERVED RESULT The exported .vcf file does not contain all all information about that contract, including tag fields. EXPECTED RESULT The exported .vcf file should contain all information that the application internally holds about the contact, including the very important, useful, and supported by the VCard standard tags feature. The beauty of having a standard is interoperability and data portativity and it would be great if Kaddressbook allowed for that. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Arch; KDE 5.17.4 (available in About System)
Categories export is explicitly disabled for VCard: https://cgit.kde.org/kcontacts.git/tree/src/vcardtool.cpp#n257 Possibly because the export would only output the internal Akonadi category IDs, which are not useful for any other non-Akonadi application or import. I had developed a fix for PIM 4 to output the category names instead, but it got overtaken by the PIM 5 release and still needs to be ported. See also bug 332358.
Thank you for the update. So it seems that this thread is essentially a duplicate from the 2014 one you linked. In any case I am quite unfamiliar with any of the technologies used in kaddressbook otherwise I could attempt migrating the patch. Given how old this is already, what could possibly be done at this stage to fix this? I'm pretty sure I'm not the only one looking to use kaddressbook as a frontend/editor of a cross-device syncronization of contacts and it's a pity that such a small issue can disrupt this potential.
Looking forward to hopefully see CATEGORIES exported in VCARD or some other manner, otherwise it would be difficult to backup anything useful. I've added a small vcard sample in bug#377223 if that helps anything here for testing.