Currently, Zanshin stores Contexts as Akonadi tags. This does not sync to other devices. Therefore, to sync also Contexts to other devices, please store them in the CATEGORIES field of vtodos <https://tools.ietf.org/html/rfc5545#section-3.8.1.2>.
Thank you for reporting this issue in KDE software. As it has been a while since this issue was reported, can we please ask you to see if you can reproduce the issue with a recent software version? If you can reproduce the issue, please change the status to "REPORTED" when replying. Thank you!
(In reply to Justin Zobel from comment #1) > Thank you for reporting this issue in KDE software. As it has been a while > since this issue was reported, can we please ask you to see if you can > reproduce the issue with a recent software version? The implementation has changed. Now the custom X-KDE-ZANSHIN-CONTEXTLIST:uuid field is used in a vtodo in combination with a vtodo with that uuid with a custom X-KDE-ZANSHIN-ISCONTEXT:1 field. This syncs to other devices, but cannot be interpreted, so the problem stays. Again, it seems to me that the CATEGORIES field of vtodos is appropriate here.