What happened: When I was returning from the settings menu, I inadvertently clicked "return to main menu". This instantly brought me back to the main menu, causing me to lose all progress with my city. Expected behaviour: there would have been some warning that all progress would be lost, and/or a prompt to save. Steps to reproduce: start game from tutorial, complete tutorial and continue to build city, open in-game menu enter settings menu, return to in-game menu, select "return to main menu".