**I used MERN(MongoDb, Express, React js, Node) technology for my app. It works locally fine. but When I deployed in heroku I am getting internal server error. I might made mistake in setup but I can't see it.**

**In google Chrome console I got this error: Refused to load the image '<https://diary2020.herokuapp.com/favicon.ico>' because it violates the following Content Security Policy directive: "default-src 'none'". Note that 'img-src' was not explicitly set, so 'default-src' is used as a fallback.**

**When I used Heroku logs I got this:**

[![enter image description here](https://i.stack.imgur.com/6zDyx.png)](https://i.stack.imgur.com/6zDyx.png)

**This is my server setup:**

```
require("dotenv").config();
const express = require("express");
const cors = require("cors");
const morgan = require("morgan");
const app = express();
const logs = require("./src/logs.js/logs");
const mongoose = require("mongoose");
const path = require("path");
const helmet = require("helmet");
//middlewares
app.use(cors());
app.use(morgan("dev"));
app.use(express.json());
app.use(helmet());

//connect to db
mongoose
  .connect(process.env.MONGODB_URI, {
    useUnifiedTopology: true,
    useNewUrlParser: true
  })
  .then(() => console.log("DB Connected!"))
  .catch(err => {
    console.log(err);
  });

app.use("/api", logs);

app.use(express.static(__dirname + "build")); //
app.get("*", (req, res) => {
  res.sendFile(path.resolve(__dirname, "build", index.html));
});

const port = process.env.PORT || 5000;

app.listen(port, () => {
  console.log(`Server is running port ${port}`);
});

```

**In my client folder first run `npm run build` then I cut it and pasted it outside of the client. Then I connected to server. As you can above. But it does not recognize the build's index.html** 

**This is my backend package.json**

```
{
  "name": "form",
  "version": "1.0.0",
  "description": "",
  "main": "server.js",
  "scripts": {
    "start": "node server.js",
    "server": "node server.js",
    "client": "npm start --prefix client",
    "dev": "concurrently \"npm run server\" \"npm run client\""
  },
  "author": "alak",
  "license": "MIT",
  "dependencies": {
    "concurrently": "^5.1.0",
    "cors": "^2.8.5",
    "dotenv": "^8.2.0",
    "express": "^4.17.1",
    "helmet": "^3.21.3",
    "heroku": "^7.39.0",
    "jquery": "^3.4.1",
    "mongoose": "^5.9.3",
    "morgan": "^1.9.1",
    "path": "^0.12.7",
    "react-router-dom": "^5.1.2", //I MISTAKENLY INSTALLED IT.BUT I THINK IT SHOULD NOT BE A PROBLEM
    "react-transition-group": "^4.3.0" //I MISTAKENLY INSTALLED IT. BUT I THINK IT SHOULD NOT BE A PROBLEM
  }
}

```

**This is React's package.json**

```
{
  "name": "client",
  "version": "0.1.0",
  "engines": {
    "node": "13.10.1",
    "npm": "6.13.7"
  },
  "private": true,
  "dependencies": {
    "@testing-library/jest-dom": "^4.2.4",
    "@testing-library/react": "^9.3.2",
    "@testing-library/user-event": "^7.1.2",
    "moment": "^2.24.0",
    "react": "^16.13.0",
    "react-dom": "^16.13.0",
    "react-scripts": "3.4.0"
  },
  "scripts": {
    "start": "react-scripts start",
    "build": "react-scripts build",
    "test": "react-scripts test",
    "eject": "react-scripts eject"
  },
  "eslintConfig": {
    "extends": "react-app"
  },
  "proxy": "http://localhost:5000",
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  }
}

```