History of HubBackend::caller 3 changes

In crates/hub/src/protocol.rs, lines 62–88 on 6ad368c5958ea7cca4655ddb3edbe0d4d00a53a3f469b861d1c1a83c33564335. Every change that wrote or deleted one of these lines, or deleted a line from between them. Exact, because each line keeps its identity across edits; edits elsewhere in the file are not here. Also: oxy log -L 62,88:crates/hub/src/protocol.rs.