It’s a bit difficult (if not extremely tedious), when we change accounts in DC, export our contacts
We are able to send more than one contact info at the same time (if not all), with the possibility to export it as vCard (or any other format) too.
afaik current method (as of DC v1.0.0) is to send a message to the recipient with contact name and a clickable email
+1 would like to export contacts only to import them in a different address, currently you can only export whole account or keys, so can’t move your contacts ex. when migrating from a google account to riseup or disroot
Maybe importing and then changing the e-mail address and password could work well enough? Most people will then see any new chat message as a contact request then. It’s at least an interesting experiment that could be the basis for improving it 
side note: this only works on Android, desktop disables the email input field once an account is configured, and I think even the python bindings don’t allow changing the email address once the account is configured, so this is kind of a hack in the Android version, I think it isn’t recommended to do so
yip 
but moving your e-mail account is not that uncommon. It’s just not a defined UX flow and functionality. but maybe it’s wrong topic here
Several months later I’m still missing the abbility to export all contacts.
Recently I lost all the info from one of my accounts, and although I have other accounts in DC, there’s no (easy) way I could share those contacts.
+1 it are very difficult in the Android version you must change the account, copy the contact, go back … Uff it are very tedious process
It would be very welcome to export all contacts to a backup file and import it again.
Even for me that function came in mind last days.
The more and the longer we use DC the more important is such a function.
One approach could be to export all data for example to a json file,
another could be to export in principle the database but without any further tables than the contacts (Contact avatars could be included).
But, as with every new function: someone has to implement a core function and a button at UI.
But, yes, I think this is an important feature! 
I think it should be in some “standard” form that would also be possible to import in other email clients or phone address book
The standard is VCard, “contacts” application on Android supports it too.
Let’s define a specification at first?
Is it possible to use one file for more than one address?
A first review of vcard format shows that one vcard can only contain one contact. Am I wrong here?
This means that this approach will product one vcard file per contact.
IMHO I think we should have a format where we can have all contacts in one file.
In Android, when I export my contacts as a vcard, it’s a single file containing hundreds of contacts.
One vcard contains info for one contact, but .vcf file can have more than one vcard inside, simply concatenated one after the other.
Yes, I did a try with Thunderbird’s adressbook export. This is exactly what Thunderbird does. It concatenates all vCards into one .vcf file
It is possible too, to choose a .csv file there. What’s the best?
.vcf is more flexible?
That would work. The possibility of exporting all/chosen contacts from DC for their use in other app or simply to make a backup will be a good feature.
Yes, IMHO vCard .vcf would be the best for doing this job. Did a try with Android contacts too.
With vCard it’s even possible to save avatars into the file
But how to save groups?
the idea is not to save groups but to save all your contact s (or maybe a selection in the contact list with option to “select all”) but well there could be an option to export group members 
currently all members of groups are added to contact list, that can add “dirty” to your contact list and most users don’t like that, it will make exporting all your “wanted contacts” more difficult
Yes, you’re right. Saving the contacts is the job. Saving groups
is not necessary and an approach of a backup!
I jumped a step too far in my mind, exucse