Testing version: iOS 10641
What were you doing: Opening the app after a while and trying see my subtags that I had previously expanded in the sidebar.
What feature did you use: iOS tag sidebar.
What happened: Apparently once the app is kicked out of memory in iOS, the app also minimizes all the expanded tags and subtags in the sidebar, even the Notes one that has Today, Archive, etc under it.
What did you expect to happen: The app to remember the state of the sidebar between cold launches like it does on macOS, and not default to all tags and their subtags to be minimized in the sidebar.