Menu music restarts when interacting with the preview button (huh!)

[Cervator]

This is a peculiar and mildly amusing bug.

Load up the game, create world screen, hit preview. As it finishes the main menu music piece restarts. Click back and it restarts again.

Seem able to navigate to other parts of the menu without a reset just fine :-)

Might be something for @msteiger to look at some time, but low priority.

[immortius]

This is likely because the preview screen causes a module environment change which triggers an asset reload - and when the music reloads it restarts. Hard to fix without creating a separate asset manager for the preview code, rather than switching the entire game's module environment.

[Cervator]

Linking to #2074