Multiple polylines on the same map fail about ivory-google-map HOT 1 OPEN

a little bit of what i've tried just for a test:

$coords[] = new Coordinate(50.45, 30.623333);
$coords[] = new Coordinate(50.45, 30.723333);
$coords[] = new Coordinate(50.45, 30.823333);

$polyline1 = new Polyline($coords, [new IconSequence(new Symbol(SymbolPath::CIRCLE))], ['fillOpacity' => 0.5]);

$map->getOverlayManager()->addPolyline($polyline1);

unset($coords);

$coords[] = new Coordinate(50.55, 30.523333);
$coords[] = new Coordinate(50.65, 30.523333);
$coords[] = new Coordinate(50.75, 30.523333);
$coords[] = new Coordinate(50.75, 30.623333);
$coords[] = new Coordinate(50.75, 30.723333);

$polyline2 = new Polyline($coords, [new IconSequence(new Symbol(SymbolPath::CIRCLE))], ['fillOpacity' => 0.5]);

// AND
$map->getOverlayManager()->addPolyline($polyline1);
$map->getOverlayManager()->addPolyline($polyline2);
// OR
$map->getOverlayManager()->addPolylines([$polyline1, $polyline2]);

// Both of variants resulted in grey screen

from ivory-google-map.