zzz-automargin-title-container.json

{
    "data": [
        {
            "showlegend": false,
            "type": "scatter",
            "x": [
            1,
            2,
            3
            ],
            "y": [
            4,
            5,
            6
            ]
        }],
    "layout": {
        "height": 300,
        "width": 400,
        "margin": {"t":0, "b": 0, "l": 0, "r": 0},
        "xaxis": {"automargin": true, "title": {"text": "x-axis title"}},
        "title": {
            "automargin": true, 
            "text": "Basic title",
            "pad": {"t": 0, "b": 0},
            "y": 0,
            "yref": "container"
        }
    }
}