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The diff is 85 lines of change and 243 lines of new tests, and I already found a few weirder edge cases that I've missed. No way I could do this well without that client-server testing setup that I posted about yesterday.

Btw I pushed the testing setup if you're curious, along with the entirety of 1215 snapshot files for a powerset of new window workspace/output target settings: https://github.com/YaLTeR/niri/commit/771ea1e81557ffe7af9cbdbec161601575b64d81

The WIP floating branch caused them to update in several commits already.

#niri