I think here is how the bug happened:
- Muscat found that volcano, however city-state cannot set name for mountain, river...
- I met Muscat but neither I nor other major players visited that volcano, it still has no name.
- I became Muscat suzerain and gained vision of all tiles muscat has visited.
=> Civ6 did not set name the moment I became Muscat suzerain.
- Without name, a volcano is never active and erupts
- Muscat found that volcano, however city-state cannot set name for mountain, river...
- I met Muscat but neither I nor other major players visited that volcano, it still has no name.
- I became Muscat suzerain and gained vision of all tiles muscat has visited.
=> Civ6 did not set name the moment I became Muscat suzerain.
- Without name, a volcano is never active and erupts
