The two rounds were meant to answer the stroke sooner, but a preview cannot be
half a repair: the blurred fill is what a machine without the runtime gets, and
with it on the stage a spot of dirt came back smeared rather than gone — worst of
all on a run of strokes, where each new one cancels the model's round that was
still on its way and leaves the blur standing longest. The repair that works is
the one that waits for the model, and the wait is worth it.
The worker stays available but is switched off with the rest: this reverts the
runtime's proxy along with the second round, so the stage is exactly what it was
before, lag and all.
Reverts 5489114.
3dtours
550e688b3c