How to setup debugging in Visual Studio Code for React Native?

I searched but I can't find any external sources except for Visual Studio Code docs, and just following those docs doesn't allow me to debug React Native apps both in iOS and Android.

I keep getting the error message (this one for Android, for iOS, is similar:

[vscode-react-native] [Warning] Couldn't import script athttp://localhost:8081/index.android.bundle?platform=android&dev=true&hot=false&minify=false.Debugging won't work: Try reloading the JS from inside the app, orReconnect the VS Code debugger: path must be a string

My launch.json file as:

{"version": "0.2.0","configurations": [        {"name": "Debug Android","program": "${workspaceRoot}/.vscode/launchReactNative.js","type": "reactnative","request": "launch","platform": "android","internalDebuggerPort": 9090,"sourceMaps": true,"outDir": "${workspaceRoot}/.vscode/.react"        },        {"name": "Debug iOS","program": "${workspaceRoot}/.vscode/launchReactNative.js","type": "reactnative","request": "launch","platform": "ios","target": "iPhone 6s","internalDebuggerPort": 9090,"sourceMaps": true,"outDir": "${workspaceRoot}/.vscode/.react"        },        {"name": "Attach to packager","program": "${workspaceRoot}/.vscode/launchReactNative.js","type": "reactnative","request": "attach","internalDebuggerPort": 9090,"sourceMaps": true,"outDir": "${workspaceRoot}/.vscode/.react"        },        {"name": "Debug in Exponent","program": "${workspaceRoot}/.vscode/launchReactNative.js","type": "reactnative","request": "launch","platform": "exponent","internalDebuggerPort": 9090,"sourceMaps": true,"outDir": "${workspaceRoot}/.vscode/.react"        }    ]}

I'm trying to debug both in the iOS simulator and in an Android device but the process never attaches to the external JS debugger.