Each section below has two boxes, the top runs on the main thread, the bottom on the compositor. The animations should be identical but start at different times.

This test is successful if the boxes are mostly in sync (there might be a small offset between them).

Iteration count 0 (should not animate)
Iteration count 0.5 (should finish first in the middle)
Iteration count 1 (should finish second at the end)
Iteration count 1.5 (should finish third in the middle)
Iteration count 2 (should finish fourth at the start)
Iteration count 2.5 (should finish last in the middle)