es6

.babelrc

@@ -0,0 +1,7 @@
+{
+    "presets": [],
+    "plugins": [
+        ["@babel/plugin-proposal-class-properties", { "loose": true }],
+        "@babel/plugin-external-helpers"
+    ]
+}

.eslintrc

@@ -57,6 +57,7 @@
             "impliedStrict": true
         }
     },
+    "parser": "babel-eslint",
     "globals": {
         "_": true,
         "$": true

package-lock.json

@@ -82,6 +82,19 @@
         "@babel/types": "^7.4.4"
       }
     },
+    "@babel/helper-create-class-features-plugin": {
+      "version": "7.6.0",
+      "resolved": "https://registry.npmjs.org/@babel/helper-create-class-features-plugin/-/helper-create-class-features-plugin-7.6.0.tgz",
+      "integrity": "sha512-O1QWBko4fzGju6VoVvrZg0RROCVifcLxiApnGP3OWfWzvxRZFCoBD81K5ur5e3bVY2Vf/5rIJm8cqPKn8HUJng==",
+      "requires": {
+        "@babel/helper-function-name": "^7.1.0",
+        "@babel/helper-member-expression-to-functions": "^7.5.5",
+        "@babel/helper-optimise-call-expression": "^7.0.0",
+        "@babel/helper-plugin-utils": "^7.0.0",
+        "@babel/helper-replace-supers": "^7.5.5",
+        "@babel/helper-split-export-declaration": "^7.4.4"
+      }
+    },
     "@babel/helper-define-map": {
       "version": "7.5.5",
       "resolved": "https://registry.npmjs.org/@babel/helper-define-map/-/helper-define-map-7.5.5.tgz",
@@ -289,6 +302,14 @@
       "resolved": "https://registry.npmjs.org/@babel/parser/-/parser-7.6.0.tgz",
       "integrity": "sha512-+o2q111WEx4srBs7L9eJmcwi655eD8sXniLqMB93TBK9GrNzGrxDWSjiqz2hLU0Ha8MTXFIP0yd9fNdP+m43ZQ=="
     },
+    "@babel/plugin-external-helpers": {
+      "version": "7.2.0",
+      "resolved": "https://registry.npmjs.org/@babel/plugin-external-helpers/-/plugin-external-helpers-7.2.0.tgz",
+      "integrity": "sha512-QFmtcCShFkyAsNtdCM3lJPmRe1iB+vPZymlB4LnDIKEBj2yKQLQKtoxXxJ8ePT5fwMl4QGg303p4mB0UsSI2/g==",
+      "requires": {
+        "@babel/helper-plugin-utils": "^7.0.0"
+      }
+    },
     "@babel/plugin-proposal-async-generator-functions": {
       "version": "7.2.0",
       "resolved": "https://registry.npmjs.org/@babel/plugin-proposal-async-generator-functions/-/plugin-proposal-async-generator-functions-7.2.0.tgz",
@@ -299,6 +320,15 @@
         "@babel/plugin-syntax-async-generators": "^7.2.0"
       }
     },
+    "@babel/plugin-proposal-class-properties": {
+      "version": "7.5.5",
+      "resolved": "https://registry.npmjs.org/@babel/plugin-proposal-class-properties/-/plugin-proposal-class-properties-7.5.5.tgz",
+      "integrity": "sha512-AF79FsnWFxjlaosgdi421vmYG6/jg79bVD0dpD44QdgobzHKuLZ6S3vl8la9qIeSwGi8i1fS0O1mfuDAAdo1/A==",
+      "requires": {
+        "@babel/helper-create-class-features-plugin": "^7.5.5",
+        "@babel/helper-plugin-utils": "^7.0.0"
+      }
+    },
     "@babel/plugin-proposal-dynamic-import": {
       "version": "7.5.0",
       "resolved": "https://registry.npmjs.org/@babel/plugin-proposal-dynamic-import/-/plugin-proposal-dynamic-import-7.5.0.tgz",
@@ -1449,6 +1479,19 @@
       "resolved": "https://registry.npmjs.org/aws4/-/aws4-1.8.0.tgz",
       "integrity": "sha512-ReZxvNHIOv88FlT7rxcXIIC0fPt4KZqZbOlivyWtXLt8ESx84zd3kMC6iK5jVeS2qt+g7ftS7ye4fi06X5rtRQ=="
     },
+    "babel-eslint": {
+      "version": "10.0.3",
+      "resolved": "https://registry.npmjs.org/babel-eslint/-/babel-eslint-10.0.3.tgz",
+      "integrity": "sha512-z3U7eMY6r/3f3/JB9mTsLjyxrv0Yb1zb8PCWCLpguxfCzBIZUwy23R1t/XKewP+8mEN2Ck8Dtr4q20z6ce6SoA==",
+      "requires": {
+        "@babel/code-frame": "^7.0.0",
+        "@babel/parser": "^7.0.0",
+        "@babel/traverse": "^7.0.0",
+        "@babel/types": "^7.0.0",
+        "eslint-visitor-keys": "^1.0.0",
+        "resolve": "^1.12.0"
+      }
+    },
     "babel-loader": {
       "version": "8.0.6",
       "resolved": "https://registry.npmjs.org/babel-loader/-/babel-loader-8.0.6.tgz",
@@ -9282,9 +9325,9 @@
       "integrity": "sha512-lv0M6+TkDVniA3aD1Eg0DVpfU/booSu7Eev3TDO/mZKHBfVjgCGTV4t4buppESEYDtkArYFOxTJWv6S5C+iaNw=="
     },
     "regexpu-core": {
-      "version": "4.5.5",
-      "resolved": "https://registry.npmjs.org/regexpu-core/-/regexpu-core-4.5.5.tgz",
-      "integrity": "sha512-FpI67+ky9J+cDizQUJlIlNZFKual/lUkFr1AG6zOCpwZ9cLrg8UUVakyUQJD7fCDIe9Z2nwTQJNPyonatNmDFQ==",
+      "version": "4.6.0",
+      "resolved": "https://registry.npmjs.org/regexpu-core/-/regexpu-core-4.6.0.tgz",
+      "integrity": "sha512-YlVaefl8P5BnFYOITTNzDvan1ulLOiXJzCNZxduTIosN17b87h3bvG9yHMoHaRuo88H4mQ06Aodj5VtYGGGiTg==",
       "requires": {
         "regenerate": "^1.4.0",
         "regenerate-unicode-properties": "^8.1.0",

package.json

@@ -11,8 +11,11 @@
     },
     "dependencies": {
         "@babel/core": "^7.6.0",
+        "@babel/plugin-external-helpers": "^7.2.0",
+        "@babel/plugin-proposal-class-properties": "^7.5.5",
         "@babel/preset-env": "^7.6.0",
         "argon2-browser": "1.10.2",
+        "babel-eslint": "^10.0.3",
         "babel-loader": "8.0.6",
         "backbone": "1.4.0",
         "baron": "3.0.3",

webpack.config.js

@@ -110,7 +110,7 @@ function config(grunt, mode = 'production') {
                     test: /\.js$/,
                     exclude: /(node_modules)/,
                     loader: 'babel-loader',
-                    query: { presets: ['@babel/preset-env'], cacheDirectory: true }
+                    query: { cacheDirectory: true }
                 },
                 { test: /argon2\.wasm/, type: 'javascript/auto', loader: 'base64-loader' },
                 { test: /argon2(\.min)?\.js/, loader: 'raw-loader' },