Two instance of React caused by injected script

Question

In our production environment a script is injected by a third party which breaks our application with React Error 321 and indeed when I run this in the console __REACT_DEVTOOLS_GLOBAL_HOOK__.renderers I see that there are two renderers, with the same version number. I suspect that this third party script is the where the second instance of React is created but I would like to know for sure. Is there any way to find out where this second React instance is coming from?

[
    {
        "key": 1,
        "value": {
            "bundleType": 0,
            "version": "16.14.0",
            "rendererPackageName": "react-dom",
            "overrideHookState": null,
            "overrideProps": null,
            "setSuspenseHandler": null,
            "scheduleUpdate": null,
            "currentDispatcherRef": {
                "current": {}
            },
            "findHostInstancesForRefresh": null,
            "scheduleRefresh": null,
            "scheduleRoot": null,
            "setRefreshHandler": null,
            "getCurrentFiber": null
        }
    },
    {
        "key": 2,
        "value": {
            "bundleType": 0,
            "version": "16.14.0",
            "rendererPackageName": "react-dom",
            "overrideHookState": null,
            "overrideProps": null,
            "setSuspenseHandler": null,
            "scheduleUpdate": null,
            "currentDispatcherRef": {
                "current": {}
            },
            "findHostInstancesForRefresh": null,
            "scheduleRefresh": null,
            "scheduleRoot": null,
            "setRefreshHandler": null,
            "getCurrentFiber": null
        }
    }
]

Answer 1

I got a similar error (You might have more than one copy of React in the same app) Can you move reactJs & react-dom to peerDependencies the package.json of imported package ?

 "peerDependencies": {
    
    "react": "^17.0.2",
    "react-dom": "^17.0.2",
    "react-router-dom": "^6.2.1"
  },