It's not really a bug, Spitfires do that in real life.
The trick is not to decelerate too fast, and it works for all planes. Besides not dragging the tail through the flip-speed zone, it helps to increase throttle till you're cruising at 65kph, then reduce as slowly as possible. The slower you go from 65 to 50, the better. Once the speed is below 50 it's safe.
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