History of Mark::step 1 change

In crates/backdrop/src/mark.rs, lines 99–105 on f993f792537e56020d40e4b598c6c384c78b10e529f307f77ef0d1304d36f68a. 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.