Network.emulateNetworkConditions在chrome 59中不能工作--无头

Question

我正在尝试通过使用以此example为起点的chrome-remote-interface在chrome --headless (chrome版本59)中模拟常规3G连接

const CDP = require('chrome-remote-interface');
const fs = require('fs');

CDP(async (client) => {
    try {
        const {Page, Tracing, Network} = client;

        Network.emulateNetworkConditions({
            offline: false,
            latency: 100,
            downloadThroughput: 750 * 1024 / 8,
            uploadThroughput: 250 * 1024 / 8
        });

        await Promise.all([Network.enable(), Page.enable()]);

        const { result } = await Network.canEmulateNetworkConditions();
        console.log(result); // always false

        // trace a page load
        const events = [];
        Tracing.dataCollected(({value}) => {
            events.push(...value);
        });
        await Tracing.start();
        await Page.navigate({url: 'https://github.com'});
        await Page.loadEventFired();
        await Tracing.end();
        await Tracing.tracingComplete();
        // save the tracing data
        fs.writeFileSync('./timeline.json', JSON.stringify(events));
    } catch (err) {
        console.error(err);
    } finally {
        await client.close();
    }
}).on('error', (err) => {
    console.error(err);
});

但Network.emulateNetworkConditions似乎不起作用。为了证明Network.canEmulateNetworkConditions()总是返回false。如果没有--headless标志，Network.canEmulateNetworkConditions()将返回true。

chrome-canary --headless (版本61)给出了相同的结果。

是我的示例包含错误还是chrome 59当前缺少此功能？