History of Mark::step 1 change

In crates/backdrop/src/mark.rs, lines 99–105 on 6246d1e51f4fdb99485662612d4148901d1456d34c65f0ecf80643da769d634e. 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 99,105:crates/backdrop/src/mark.rs.