browsersync rewriterules not used

.gitignore

node_modules

app-index.html

<!-- Put this file in 'app/index.html', not 'app-index.html' -->
Hello World

index.js

var bs = require("browser-sync").create();

bs.init({
  server: "./app",
  rewriteRules: [
    {
      match: /Hello/ig,
      fn: function(match) {
        console.log('MATCH!!!!');
        return 'Cello';
      },
    },
    {
      match: 'Hello',
      replace: 'Shmello',
    },
  ],
});

package.json

{
  "name": "browsersync-bug",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "dependencies": {
    "browser-sync": "^2.9.11"
  }
}