This should be obvious, but I can't see how to do it. Just want the project browser to stay in sync with the current file I'm editing.
I'm using IdeaVIM plugin in case that's causing any issues, though I think it's just default value not to sync.
Project view has an option to Autoscroll from Source under the Gear icon. If you prefer manual sync, use Navigate | Select In... menu or the corresponding keyboard shortcut.