When editing tags for a contact, kaddressbook uses a dialog that I suspect comes from nepomuk. This dialog comes with an option to delete a tag, in the GUI represented by a rec X in the right side of the tag in the list. Clicking it, I am asked wheather to remove the tag "from all files". I say yes, and probably, a nepomuk query removes the tag from all files and deletes it.

But the tag is not removed from all contacts.

Instead, contacts that use the tag, now appears to have a unnamed tag - sometimes more, if more tags was removed. Now, edting such a contacts categories leads to a horrible state, namely the display of categories named "nepomuk:/resource=woihtrwlgjrdlfgbdf" or thereabout. How embarassing!

It seems to me, that when the nepomuk tag is removed, action should be taken to remove the corresponding category from all contacts. 

Reproducible: Always

Steps to Reproduce:
1. add some tags to some contacts
2. wait for it to apply throughout the chain
3. edit a contact categries, and use the option to remove a tag. Accept to remove the tag "from all files"
4. edit the tags of a contact which now have empty tags, check or uncheck other tags than the anonymous one[s]
Actual Results:  
some contacts have empty tags.
the contact edited in step 4 have tags named "nepomuk:/...."

Expected Results:  
the removed tag should be removed for real, and no empty/anonymous tags should exist.

My address books are stored in owncloud, but this also affects local addressbooks using vcard files