---
features:
  - |
    The new API extension ``extraroute-atomic`` introduces two new member
    actions on routers to add/remove routes atomically on the server side.
    The use of these new member actions
    (``PUT /v2.0/routers/ROUTER-ID/add_extraroutes`` and
    ``PUT /v2.0/routers/ROUTER-ID/remove_extraroutes``) is always preferred
    to the old way (``PUT /v2.0/routers/ROUTER-ID``) when multiple clients
    edit the extra routes of a router since the old way is prone to race
    conditions between concurrent clients and therefore to possible lost
    updates.
