Just like in classic RPG's where walking around in a grassy area might trigger some combat, now walking around in the world has a chance of triggering an interruption. The interruption will manifest in the form of a story turn and all the usual event checks (e.g. gained an item, new character appeared, etc) apply.
During fast travel, the game will simulate walking through a path that takes you from point A to B, and at each point you have a chance of triggering this interruption. The frequency as well as maximum probability while fast traveling can be configured in the options.
Misc: Hopefully fixed a steam deck compatibility issue