History of Mark::step 1 change

In crates/backdrop/src/mark.rs, lines 101–107 on 166f6e9bf4f134de4e0de65a2d4453aa82c04cbcff14f3854bb7e8a7ee361182. 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 101,107:crates/backdrop/src/mark.rs.