In Terra Incognita, razing the starting city while having 3 other territories and no other city would trigger "you now have city of 10 territories" narration.
Step by step of the bug
Step 1
In Terra Incognita, start as Ming
Step 2
Settle 3 territories
Step 3
Finish Three-Mast Ship
Step 4
Finish razing the only city at the same turn start
Step 5
Narration: "you now have a city with 10 territories" while actually no city and no 10 territories
In Terra Incognita, razing the starting city while having 3 other territories and no other city would trigger "you now have city of 10 territories" narration.