1.30 BUG Ship missing from properties (savegame joined)

[Ethann]

- 1.30, french localisation (savegame in 1.21, but the bug still here)
- Game not modified
- Start : Argon
- Properties are totaly empty, the only vessel owned don't show up in it

I'm actually reporting this issue from french technical support, from someone not comfortable in English, I do it for him.
Link to Original thread (no complementary relevant information in here, is just for record)

There is his savegame : https://www.partage-fichiers.com/upload/nfy2p9c7/

Somehow the only ship owned have by default an escort behavior seted on an unknow element, maybe it's the source with problem due to subordination who caused the disappearance?
Reset the default behavior don't resolve anything.
I tryed to sell the ship and buy another one, no problem occured, so i can't reproduice the bug and don't do more testing.