1.在VS Code中安装Debugger for Firefox插件

2.下载安Firefox Developer Edition

3. 创建launch.json

编辑并保存launch.json

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Launch MyDraw.html",
            "type": "firefox",
            "request": "launch",
            "reAttach": true,
            "file": "${workspaceFolder}/MyDraw.html"
        }
    ]
}

4.开始调试

5.设置断点开始调试，html中的javasript的代码也可以调试