Echarts 4 graph plot: specify symbol per category - echarts

Question

I am trying to create a graph plot in Echarts 4, where each node belongs to one of two categories: https://codepen.io/autarkie/pen/LqqZjM:
var nodes = [{
"id": 1,
"category": 1
}, {
"id": 2,
"category": 0
}, {
"id": 3,
"category": 1
}, {
"id": 4,
"category": 0
}];
var links = [{
"source": "3",
"target": "1"
}, {
"source": "3",
"target": "2"
}, {
"source": "1",
"target": "2"
}, {
"source": "2",
"target": "4"
}];
var myChart = echarts.init(document.getElementById('chart'));
var option = {
backgroundColor: new echarts.graphic.RadialGradient(0.4, 0.4, 0.7, [{
offset: 0,
color: '#162436'
}, {
offset: 1,
color: '#000'
}]),
legend: {
data: ["Type 1", "Type 2"],
textStyle: {
color: '#fff'
},
icon: 'circle',
type: 'scroll',
orient: 'vertical',
left: 10,
top: 20,
bottom: 20,
itemWidth: 10,
itemHeight: 10
},
animationDurationUpdate: 300,
animationEasingUpdate: 'quinticInOut',
series: [{
type: 'graph',
layout: 'force',
// symbol: 'rect',
//symbolSize: 10,
lineStyle: {
normal: {
curveness: 0.1
}
},
roam: true,
focusNodeAdjacency: true,
legendHoverLink: true,
draggable: true,
force: {
repulsion: 30,
gravity: 0.03,
edgeLength: 50,
layoutAnimation: true
},
data: nodes,
links: links,
categories: [{
name: 'Type 1',
symbol: 'diamond', // !!! DOES NOT WORK !!!
symbolSize: 30, // !!! DOES NOT WORK !!!
itemStyle: {
color: '#79d2a6'
}
},
{
name: 'Type 2',
symbol: "rect", // DOES NOT WORK
symbolSize: 20, // DOES NOT WORK
itemStyle: {
color: '#ff9900'
}
}
],
}]
};
myChart.setOption(option);
Each category should have its own symbol. I know it is possible to specify the symbol for each node separately, like so:
var node_shaped = [{
"id": 1,
"symbol": "rect",
"category": 1
}]
but it this is quite inelegant. Echarts documentation (https://ecomfe.github.io/echarts-doc/public/en/option.html#series-graph.categories.symbol) specifies the option to include a symbol per category, like in the code above. However, that option has no effect whatsoever on the node shapes. Instead, the default circle shape is used. It is possible to change category color using a similar category-wide option, so I am at loss as to why the shape specification doesn't work. Thanks for taking a look.