Add package.json, add eslint and format the whole files

.eslintrc.json

@@ -0,0 +1,39 @@
+{
+  "env": {
+    "browser": true,
+    "es2021": true
+  },
+  "extends": "eslint:recommended",
+  "overrides": [
+    {
+      "files": ["packed.js"],
+      "rules": {
+        "no-unused-vars": "error",
+        "no-undef": "error"
+      }
+    }
+  ],
+  "parserOptions": {
+    "ecmaVersion": "latest"
+  },
+  "rules": {
+    "indent": [
+      "error",
+      4
+    ],
+    "linebreak-style": [
+      "error",
+      "windows"
+    ],
+    "quotes": [
+      "error",
+      "single"
+    ],
+    "semi": [
+      "error",
+      "always"
+    ],
+    "no-undef": "off",
+    "no-unused-vars": "off"
+  }
+}

.gitignore

@@ -128,5 +128,3 @@ dist
 .yarn/install-state.gz
 .pnp.*
 .idea
-/package.json
-/package-lock.json

Gruntfile.js

@@ -2,9 +2,14 @@ module.exports = function(grunt) {
     grunt.initConfig({
         concat: {
             options: {
-                banner: 'window.plus_main = () => {\n',
-                footer: '\n};\nif (!window.is_plus_loaded) {\n\twindow.is_plus_loaded = true;\n\twindow.plus_main()\n}',
+                banner: '/* global require */\nwindow.plus_main = () => {\n',
+                footer: '\n};\nif (!window.is_plus_loaded) {\n    window.is_plus_loaded = true;\n    window.plus_main();\n}',
                 separator: '\n\n',
+                process: function(file) {
+                    return file.split('\n').map(function(line) {
+                        return '    ' + line;
+                    }).join('\n');
+                }
             },
             dist: {
                 src: [

index.js

@@ -14,7 +14,7 @@ function handle_settings_update(settings) {
 inject_script('packed.js');
 
 
-chrome.storage.sync.onChanged.addListener(function (changes, namespace) {
+chrome.storage.sync.onChanged.addListener(function (changes) {
     if (changes?.settings !== undefined) {
         handle_settings_update(changes.settings.newValue);
     }