Today I merged a PR by FluxTape which adds "always empty workspace before first" to niri. At the surface this is just a simple config flag with obvious behavior, but it's actually full of edge cases! Things like which workspace to focus at startup. The code refers to workspaces by index in many places, and those all shift when you suddenly insert an empty workspace at index 0.
Took several days to catch them all even with our randomized tests, but I think it should be good now.