Per Support, "In Smartsheet, collapsed/expanded row states should ideally persist across sessions. Saving a sheet with collapsed rows should retain that state upon reloading. Parent row expansion/collapse should be controlled by the saved state. For example, saving a sheet with all child rows collapsed should, upon reloading, display only the parent rows. Conversely, saving with child rows expanded should retain that view. However, in collaborative environments, the view displayed upon reload will reflect the last saved state. If a collaborator saves the sheet with rows expanded, that expanded view will be what all users see upon reloading."
I would like this to be improved upon, by my preferred expand/collapse retaining for me regardless of what other shared users are looking at. I would like the expand/collapse view to be per person, not shared for the whole sheet/all users.