Option-constrained fields no longer offer ways to set an invalid value. For a field limited to a fixed, predefined set of options, the menu no longer shows “Search…” or “New…”, since either could set a value outside the allowed set - and this now holds however the menu is opened, including the right-click menu on a field whose arrow opens a dropdown. A relation that is merely narrowed by an option query is not treated as such a fixed list: it keeps “Search…” and “New…”, and its dropdown search now applies that option query so only the permitted records are offered. When a field's allowed options resolve to an empty set, the menu shows a disabled “No matches” rather than appearing empty. Together with the valid-only filtering above, every choice the menu offers stays within the field's permitted options.