History of Colour::class 1 change

In crates/hub/src/diffusion.rs, lines 245–254 on 9a8e3b4419e05574a3a5bb5d37fda6b1d904fb842bf91608237fd4b0699b758e. 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 245,254:crates/hub/src/diffusion.rs.