issue2551196 - Unset labelprop of a Multilink can lead to Python error when using context/history Fix history by adding default string value to calls to link_class.get(). Mark as translatable string. Include originally identified multilink path and apply same fix to link path. Also fix a possible issue in the plain() display paths for link/multilink the same way if the label is missing. Update translation files.

try:
    # Python 3+.
    from xmlrpc import client, server
    server.SimpleXMLRPCDispatcher
except (ImportError, AttributeError):
    # Python 2.
    import xmlrpclib as client  # noqa: F401
    import SimpleXMLRPCServer as server