Hi,
It is unclear, but the auto complete allows the usage of IPv6 onto L2TPv3 and commiting does not give any errors. However after that the interface is broken and does not come online. As a result i cannot delete it afterwords:
[ interfaces l2tpv3 l2tpeth1010 ]
RTNETLINK answers: No such device
RTNETLINK answers: No such device
delete [ interfaces l2tpv3 l2tpeth1010 ] failed
Commit failed
to reproduce, us the example from manual and replace local/remote IP's with IPv6.