Noticed another bug today (or at least I assume it's one), screenshots below:
There's a hostile Advent envoy in my system autocasting the envoy buffs (in this shot it's the logistics cost reduction, but it was also casting the bombing invulnerability). Now I know they can do this even for hostile players to gain reputation, but in this case it was a locked teams game and they were also bombing the crap out of my planet, so it really doesn't seem to make much sense.
Come to think of it, the AI shouldn't send these to enemy systems at all in locked team games. I've seen it do this for long as I've been playing Diplomacy so I guess that isn't a new issue though. At the very least though, they really shouldn't sabotage their own pushes by making the planet they're targeting invulnerable with their envoys...
I have a save game if it's necessary, but it doesn't seem like this would be hard to reproduce.