box2d: Body not slowing down with friction for static body (Bug)

It seems like there’s a bug in the following set-up, reproducible by with the default settings and Step(1/60f, 8, 8) (not the test-bed settings):

b2Vec2 gravity;
gravity.Set(0.0f, -10.0f);
m_world = new b2World(gravity);
b2ChainShape chainShape;
b2Vec2 vertices[] = {b2Vec2(-5,0), b2Vec2(5,0), b2Vec2(5,5), b2Vec2(4,1), b2Vec2(-4,1), b2Vec2(-5,5)};
chainShape.CreateLoop(vertices, 6);

b2FixtureDef groundFixtureDef;
groundFixtureDef.density = 0;
groundFixtureDef.shape = &chainShape;

b2BodyDef groundBodyDef;
groundBodyDef.type = b2_staticBody;

b2Body *groundBody = m_world->CreateBody(&groundBodyDef);
b2Fixture *groundBodyFixture = groundBody->CreateFixture(&groundFixtureDef);

b2CircleShape ballShape;
ballShape.m_radius = 1;

b2FixtureDef ballFixtureDef;
ballFixtureDef.restitution = 0.75f;
ballFixtureDef.density = 1;
ballFixtureDef.shape = &ballShape;

b2BodyDef ballBodyDef;
ballBodyDef.type = b2BodyType::b2_dynamicBody;
ballBodyDef.position = b2Vec2(0, 10);

b2Body *ball = m_world->CreateBody(&ballBodyDef);
b2Fixture *ballFixture = ball->CreateFixture(&ballFixtureDef);
ball->ApplyForceToCenter(b2Vec2(-1000, -400), true);

As you’ll see the ball at the end is meant to stop and in fact, if you choose the ground to be dynamic body instead of static, the ball will stop, but when it’s dynamic and the ball is supposed to stop it will pick up speed. Doesn’t seem related to the recent changes with density zero improvement. I was able to repro it even in previous commits to that.