Answer
On the 'Database Objects' and 'Presentation Objects by Component' tabs, blue text means the object is only PARTIALLY granted, while black text means it's FULLY granted. On the separate 'Presentation Objects by Navigator' tab, the same colors mean something subtly different: blue there specifically means 'Granted Query' (view-only access, itself a form of partial grant), while black means 'Granted' (full access) — though a black 'Granted' entry there can still actually be partial once you check its underlying Details pane, depending on whether specific screen components are native to that screen or actually shared with a different one, which is reflected there by italicized versus non-italicized entries. Separately, a filled-in diamond icon represents a PROCEDURE, and a non-filled, outline-only diamond represents a FUNCTION.