After an upgrade from R77.30 to R80.20, RIP neighbor traffic does not work, and all the routes from the routers are missing.
When SecureXLis disabled, the neighbor traffic is working again.
For routers which use RIPv1, there is no issue.
Changing the router configuration to work with RIPv2 only, the issue is coming back.
RIPv2 packets has TTL=2, and the Security Gateway is trying to accelerate RIPv2 packets if the ttl < 1, which is incorrect.