.eslintrc.json

{
    "root": true,
    "env": {
        "browser": true,
        "es6": true,
        "webextensions": true
    },
    "parserOptions": {
        "ecmaVersion": 2017
    },
    "extends": "eslint:recommended",
    "rules": {
        "indent": [
            "warn",
            4,
            {"SwitchCase": 1}
        ],
        "linebreak-style": [
            "warn",
            "windows"
        ],
        "quotes": [
            "error",
            "double"
        ],
        "semi": [
            "error",
            "always",
            {"omitLastInOneLineBlock": true}
        ],
        "semi-spacing": "error",
        "no-prototype-builtins": "off",
        "no-redeclare": ["error", {"builtinGlobals": false}],
        "no-trailing-spaces": "error",
        "no-tabs": "error",
        "no-unused-vars": ["error", {"vars": "local"}],
        "no-multi-spaces": ["warn", { "ignoreEOLComments": false }],
        "space-infix-ops": "warn",
        "space-before-blocks": "warn",
        "key-spacing": "warn",
        "block-spacing": "warn",
        "array-bracket-spacing": "warn",
        "object-curly-spacing": "warn",
        "computed-property-spacing": "warn",
        "comma-spacing": "warn",
        "space-before-function-paren": ["warn", "never"],
        "spaced-comment": "warn",
        "array-bracket-newline": ["warn", { "multiline": true }],
        "object-curly-newline": ["warn", { "multiline": true }],
        "object-property-newline": ["warn", { "allowAllPropertiesOnSameLine": true }],
        "comma-dangle": "warn",
        "comma-style": "error",
        "brace-style": ["error", "stroustrup", { "allowSingleLine": true }]
    }
}