v3: Fix the broken process DPI awareness initialization from the application manifest, which should fix the builtin applications too. Also compensate rounding a bit in exposed rectangle, which should fix the 1px lines.
Fwiw there's still some minor scaling artifacts with very large factors but I believe this is caused by the partial bilinear filtering, which I tried to compensate before by rounding the flushed rectangle up a bit, but that's not good enough. It's not much noticeable though, so hopefully not a big deal. I think we could do better scaling would need with accelerated compositing, but that'll need more work.