diff --git a/.gitignore b/.gitignore
index 29432c99..8b786b66 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,4 @@ node_modules/
 package-lock.json
 yarn.lock
 *.zip
+.eslintcache
diff --git a/background/parserlib-loader.js b/background/parserlib-loader.js
new file mode 100644
index 00000000..8275e8fd
--- /dev/null
+++ b/background/parserlib-loader.js
@@ -0,0 +1,9 @@
+/* global importScripts parserlib CSSLint parseMozFormat */
+'use strict';
+
+importScripts('/vendor-overwrites/csslint/parserlib.js', '/js/moz-parser.js');
+parserlib.css.Tokens[parserlib.css.Tokens.COMMENT].hide = false;
+
+self.onmessage = ({data}) => {
+  self.postMessage(parseMozFormat(data));
+};
diff --git a/edit.html b/edit.html
index d99c00c9..8463a984 100644
--- a/edit.html
+++ b/edit.html
@@ -25,7 +25,6 @@
     <script src="js/script-loader.js"></script>
     <script src="js/storage-util.js"></script>
     <script src="content/apply.js"></script>
-    <script src="edit/lint.js"></script>
     <script src="edit/util.js"></script>
     <script src="edit/regexp-tester.js"></script>
     <script src="edit/applies-to-line-widget.js"></script>
@@ -65,6 +64,8 @@
     <script src="vendor/codemirror/addon/fold/comment-fold.js"></script>
 
     <link  href="vendor/codemirror/addon/lint/lint.css" rel="stylesheet" />
+    <script src="vendor/codemirror/addon/lint/lint.js"></script>
+
 
     <link  href="vendor/codemirror/addon/hint/show-hint.css" rel="stylesheet" />
     <script src="vendor/codemirror/addon/hint/show-hint.js"></script>
@@ -87,6 +88,16 @@
     <link  href="edit/codemirror-default.css" rel="stylesheet">
     <script src="edit/codemirror-default.js"></script>
 
+    <script src="edit/linter.js"></script>
+    <script src="edit/linter-defaults.js"></script>
+    <script src="edit/linter-engines.js"></script>
+    <script src="edit/linter-meta.js"></script>
+    <script src="edit/linter-help-dialog.js"></script>
+    <script src="edit/linter-report.js"></script>
+    <script src="edit/linter-config-dialog.js"></script>
+
+    <script src="edit/editor-worker.js"></script>
+
     <link id="cm-theme" rel="stylesheet">
 
     <template data-id="appliesTo">
@@ -417,7 +428,7 @@
             </a>
           </h2>
         </summary>
-        <div></div>
+        <div class="lint-report-container"></div>
       </details>
       <div id="footer" class="hidden">
         <a href="https://github.com/openstyles/stylus/wiki/Usercss"
diff --git a/edit/codemirror-editing-hooks.js b/edit/codemirror-editing-hooks.js
index a53bf618..2ad0a310 100644
--- a/edit/codemirror-editing-hooks.js
+++ b/edit/codemirror-editing-hooks.js
@@ -1,5 +1,5 @@
 /*
-global CodeMirror linterConfig loadScript
+global CodeMirror loadScript
 global editors editor styleId ownTabId
 global save toggleStyle setupAutocomplete makeSectionVisible getSectionForChild
 global getSectionsHashes
@@ -8,9 +8,6 @@ global messageBox
 'use strict';
 
 onDOMscriptReady('/codemirror.js').then(() => {
-
-  CodeMirror.defaults.lint = linterConfig.getForCodeMirror();
-
   const COMMANDS = {
     save,
     toggleStyle,
diff --git a/edit/csslint-loader.js b/edit/csslint-loader.js
deleted file mode 100644
index dfe7811f..00000000
--- a/edit/csslint-loader.js
+++ /dev/null
@@ -1,41 +0,0 @@
-/* global importScripts parserlib CSSLint parseMozFormat */
-'use strict';
-
-const CSSLINT_PATH = '/vendor-overwrites/csslint/';
-importScripts(CSSLINT_PATH + 'parserlib.js');
-
-parserlib.css.Tokens[parserlib.css.Tokens.COMMENT].hide = false;
-
-self.onmessage = ({data}) => {
-
-  const {action = 'run'} = data;
-
-  if (action === 'parse') {
-    if (!self.parseMozFormat) self.importScripts('/js/moz-parser.js');
-    self.postMessage(parseMozFormat(data));
-    return;
-  }
-
-  if (!self.CSSLint) self.importScripts(CSSLINT_PATH + 'csslint.js');
-
-  switch (action) {
-    case 'getAllRuleIds':
-      // the functions are non-tranferable and we need only an id
-      self.postMessage(CSSLint.getRules().map(rule => rule.id));
-      return;
-
-    case 'getAllRuleInfos':
-      // the functions are non-tranferable
-      self.postMessage(CSSLint.getRules().map(rule => JSON.parse(JSON.stringify(rule))));
-      return;
-
-    case 'run': {
-      const {code, config} = data;
-      const results = CSSLint.verify(code, config).messages
-        //.filter(m => !m.message.includes('/*[[') && !m.message.includes(']]*/'))
-        .map(m => Object.assign(m, {rule: {id: m.rule.id}}));
-      self.postMessage(results);
-      return;
-    }
-  }
-};
diff --git a/edit/edit.css b/edit/edit.css
index 684a5757..5481bb08 100644
--- a/edit/edit.css
+++ b/edit/edit.css
@@ -651,6 +651,9 @@ body[data-match-highlight="selection"] .CodeMirror-selection-highlight-scrollbar
 #lint table:last-child {
   margin-bottom: 0;
 }
+#lint table.empty {
+  display: none;
+}
 #lint caption {
   text-align: left;
   font-weight: bold;
diff --git a/edit/edit.js b/edit/edit.js
index 8e62f9c6..796af1db 100644
--- a/edit/edit.js
+++ b/edit/edit.js
@@ -1,13 +1,12 @@
 /*
-global CodeMirror parserlib loadScript
-global CSSLint initLint linterConfig updateLintReport renderLintReport updateLinter
+global CodeMirror loadScript
 global createSourceEditor
 global closeCurrentTab regExpTester messageBox
 global setupCodeMirror
 global beautify
 global initWithSectionStyle addSections removeSection getSectionsHashes
 global sectionsToMozFormat
-global moveFocus
+global moveFocus editorWorker
 */
 'use strict';
 
@@ -212,7 +211,6 @@ function beforeUnload() {
   }
   const isDirty = editor ? editor.isDirty() : !isCleanGlobal();
   if (isDirty) {
-    updateLintReportIfEnabled(null, 0);
     // neither confirm() nor custom messages work in modern browsers but just in case
     return t('styleChangesNotSaved');
   }
@@ -276,9 +274,6 @@ function initHooks() {
   $('#save-button').addEventListener('click', save, false);
   $('#sections-help').addEventListener('click', showSectionHelp, false);
 
-  // TODO: investigate why FF needs this delay
-  debounce(initLint, FIREFOX ? 100 : 0);
-
   if (!FIREFOX) {
     $$([
       'input:not([type])',
@@ -353,7 +348,6 @@ function toggleStyle() {
 }
 
 function save() {
-  updateLintReportIfEnabled(null, 0);
   if (!validate()) {
     return;
   }
@@ -414,12 +408,6 @@ function updateTitle() {
   $('#save-button').disabled = clean;
 }
 
-function updateLintReportIfEnabled(...args) {
-  if (CodeMirror.defaults.lint) {
-    updateLintReport(...args);
-  }
-}
-
 function showMozillaFormat() {
   const popup = showCodeMirrorPopup(t('styleToMozillaFormatTitle'), '', {readOnly: true});
   popup.codebox.setValue(toMozillaFormat());
@@ -461,16 +449,7 @@ function fromMozillaFormat() {
 
   function doImport({replaceOldStyle = false}) {
     lockPageUI(true);
-    new Promise(setTimeout)
-      .then(() => {
-        const worker = linterConfig.worker.csslint;
-        if (!worker.instance) worker.instance = new Worker(worker.path);
-      })
-      .then(() => linterConfig.invokeWorker({
-        linter: 'csslint',
-        action: 'parse',
-        code: popup.codebox.getValue().trim(),
-      }))
+    editorWorker.parseMozFormat({code: popup.codebox.getValue().trim()})
       .then(({sections, errors}) => {
         // shouldn't happen but just in case
         if (!sections.length && errors.length) {
@@ -483,8 +462,7 @@ function fromMozillaFormat() {
         removeOldSections(replaceOldStyle);
         return addSections(sections, div => setCleanItem(div, false));
       })
-      .then(sectionDivs => {
-        sectionDivs.forEach(div => updateLintReportIfEnabled(div.CodeMirror, 1));
+      .then(() => {
         $('.dismiss').dispatchEvent(new Event('click'));
       })
       .catch(showError)
@@ -604,7 +582,6 @@ function showCodeMirrorPopup(title, html, options) {
     foldGutter: true,
     gutters: ['CodeMirror-linenumbers', 'CodeMirror-foldgutter', 'CodeMirror-lint-markers'],
     matchBrackets: true,
-    lint: linterConfig.getForCodeMirror(),
     styleActiveLine: true,
     theme: prefs.get('editor.theme'),
     keyMap: prefs.get('editor.keyMap')
diff --git a/edit/editor-worker-body.js b/edit/editor-worker-body.js
new file mode 100644
index 00000000..a4458dd6
--- /dev/null
+++ b/edit/editor-worker-body.js
@@ -0,0 +1,118 @@
+/* global importScripts parseMozFormat parserlib CSSLint require */
+'use strict';
+
+createAPI({
+  csslint: (code, config) => {
+    loadParserLib();
+    loadScript(['/vendor-overwrites/csslint/csslint.js']);
+    return CSSLint.verify(code, config).messages
+      .map(m => Object.assign(m, {rule: {id: m.rule.id}}));
+  },
+  stylelint: (code, config) => {
+    loadScript(['/vendor/stylelint-bundle/stylelint-bundle.min.js']);
+    return require('stylelint').lint({code, config});
+  },
+  parseMozFormat: data => {
+    loadParserLib();
+    loadScript(['/js/moz-parser.js']);
+    return parseMozFormat(data);
+  },
+  getStylelintRules,
+  getCsslintRules
+});
+
+function getCsslintRules() {
+  loadScript(['/vendor-overwrites/csslint/csslint.js']);
+  return CSSLint.getRules().map(rule => {
+    const output = {};
+    for (const [key, value] of Object.entries(rule)) {
+      if (typeof value !== 'function') {
+        output[key] = value;
+      }
+    }
+    return output;
+  });
+}
+
+function getStylelintRules() {
+  loadScript(['/vendor/stylelint-bundle/stylelint-bundle.min.js']);
+  const stylelint = require('stylelint');
+  const options = {};
+  const rxPossible = /\bpossible:("(?:[^"]*?)"|\[(?:[^\]]*?)\]|\{(?:[^}]*?)\})/g;
+  const rxString = /"([-\w\s]{3,}?)"/g;
+  for (const id of Object.keys(stylelint.rules)) {
+    const ruleCode = String(stylelint.rules[id]);
+    const sets = [];
+    let m, mStr;
+    while ((m = rxPossible.exec(ruleCode))) {
+      const possible = m[1];
+      const set = [];
+      while ((mStr = rxString.exec(possible))) {
+        const s = mStr[1];
+        if (s.includes(' ')) {
+          set.push(...s.split(/\s+/));
+        } else {
+          set.push(s);
+        }
+      }
+      if (possible.includes('ignoreAtRules')) {
+        set.push('ignoreAtRules');
+      }
+      if (possible.includes('ignoreShorthands')) {
+        set.push('ignoreShorthands');
+      }
+      if (set.length) {
+        sets.push(set);
+      }
+    }
+    if (sets.length) {
+      options[id] = sets;
+    }
+  }
+  return options;
+}
+
+function loadParserLib() {
+  if (typeof parserlib !== 'undefined') {
+    return;
+  }
+  importScripts('/vendor-overwrites/csslint/parserlib.js');
+  parserlib.css.Tokens[parserlib.css.Tokens.COMMENT].hide = false;
+}
+
+const loadedUrls = new Set();
+function loadScript(urls) {
+  urls = urls.filter(u => !loadedUrls.has(u));
+  importScripts(...urls);
+  urls.forEach(u => loadedUrls.add(u));
+}
+
+function createAPI(methods) {
+  self.onmessage = e => {
+    const message = e.data;
+    Promise.resolve()
+      .then(() => methods[message.action](...message.args))
+      .then(result => ({
+        id: message.id,
+        error: false,
+        data: result
+      }))
+      .catch(err => ({
+        id: message.id,
+        error: true,
+        data: cloneError(err)
+      }))
+      .then(data => self.postMessage(data));
+  };
+}
+
+function cloneError(err) {
+  return Object.assign({
+    name: err.name,
+    stack: err.stack,
+    message: err.message,
+    lineNumber: err.lineNumber,
+    columnNumber: err.columnNumber,
+    fileName: err.fileName
+  }, err);
+}
diff --git a/edit/editor-worker.js b/edit/editor-worker.js
new file mode 100644
index 00000000..1323ea72
--- /dev/null
+++ b/edit/editor-worker.js
@@ -0,0 +1,39 @@
+'use strict';
+
+// eslint-disable-next-line no-var
+var editorWorker = (() => {
+  let worker;
+  return new Proxy({}, {
+    get: (target, prop) =>
+      (...args) => {
+        if (!worker) {
+          worker = createWorker();
+        }
+        return worker.invoke(prop, args);
+      }
+  });
+
+  function createWorker() {
+    let id = 0;
+    const pendingResponse = new Map();
+    const worker = new Worker('/edit/editor-worker-body.js');
+    worker.onmessage = e => {
+      const message = e.data;
+      pendingResponse.get(message.id)[message.error ? 'reject' : 'resolve'](message.data);
+      pendingResponse.delete(message.id);
+    };
+    return {invoke};
+
+    function invoke(action, args) {
+      return new Promise((resolve, reject) => {
+        pendingResponse.set(id, {resolve, reject});
+        worker.postMessage({
+          id,
+          action,
+          args
+        });
+        id++;
+      });
+    }
+  }
+})();
diff --git a/edit/lint-codemirror-helper.js b/edit/lint-codemirror-helper.js
deleted file mode 100644
index 90555533..00000000
--- a/edit/lint-codemirror-helper.js
+++ /dev/null
@@ -1,43 +0,0 @@
-/* global CodeMirror linterConfig */
-'use strict';
-
-(() => {
-  CodeMirror.registerHelper('lint', 'csslint', invokeHelper);
-  CodeMirror.registerHelper('lint', 'stylelint', invokeHelper);
-
-  const COOKS = {
-    csslint: results =>
-      results.map(({line, col: ch, message, rule, type: severity}) => line && {
-        message,
-        from: {line: line - 1, ch: ch - 1},
-        to: {line: line - 1, ch},
-        rule: rule.id,
-        severity,
-      }).filter(Boolean),
-
-    stylelint({results}, cm) {
-      if (!results[0]) return [];
-      const output = results[0].warnings.map(({line, column: ch, text, severity}) => ({
-        from: {line: line - 1, ch: ch - 1},
-        to: {line: line - 1, ch},
-        message: text
-          .replace('Unexpected ', '')
-          .replace(/^./, firstLetter => firstLetter.toUpperCase())
-          .replace(/\s*\([^(]+\)$/, ''), // strip the rule,
-        rule: text.replace(/^.*?\s*\(([^(]+)\)$/, '$1'),
-        severity,
-      }));
-      return cm.doc.mode.name !== 'stylus' ?
-        output :
-        output.filter(({message}) =>
-          !message.includes('"@css"') || !message.includes('(at-rule-no-unknown)'));
-    },
-  };
-
-  function invokeHelper(code, options, cm) {
-    const config = linterConfig.getCurrent();
-    const cook = COOKS[linterConfig.getName()];
-    return linterConfig.invokeWorker({code, config})
-      .then(data => cook(data, cm));
-  }
-})();
diff --git a/edit/lint-defaults-csslint.js b/edit/lint-defaults-csslint.js
deleted file mode 100644
index 465a8215..00000000
--- a/edit/lint-defaults-csslint.js
+++ /dev/null
@@ -1,50 +0,0 @@
-'use strict';
-
-/**
- * CSSLint Config values
- * 0 = disabled; 1 = warning; 2 = error
- */
-window.linterConfig.defaults.csslint = {
-  // Default warnings
-  'display-property-grouping': 1,
-  'duplicate-properties': 1,
-  'empty-rules': 1,
-  'errors': 1,
-  'warnings': 1,
-  'known-properties': 1,
-
-  // Default disabled
-  'adjoining-classes': 0,
-  'box-model': 0,
-  'box-sizing': 0,
-  'bulletproof-font-face': 0,
-  'compatible-vendor-prefixes': 0,
-  'duplicate-background-images': 0,
-  'fallback-colors': 0,
-  'floats': 0,
-  'font-faces': 0,
-  'font-sizes': 0,
-  'gradients': 0,
-  'ids': 0,
-  'import': 0,
-  'import-ie-limit': 0,
-  'important': 0,
-  'order-alphabetical': 0,
-  'outline-none': 0,
-  'overqualified-elements': 0,
-  'qualified-headings': 0,
-  'regex-selectors': 0,
-  'rules-count': 0,
-  'selector-max': 0,
-  'selector-max-approaching': 0,
-  'selector-newline': 0,
-  'shorthand': 0,
-  'star-property-hack': 0,
-  'text-indent': 0,
-  'underscore-property-hack': 0,
-  'unique-headings': 0,
-  'universal-selector': 0,
-  'unqualified-attributes': 0,
-  'vendor-prefix': 0,
-  'zero-units': 0
-};
diff --git a/edit/lint-defaults-stylelint.js b/edit/lint-defaults-stylelint.js
deleted file mode 100644
index b75bf6f4..00000000
--- a/edit/lint-defaults-stylelint.js
+++ /dev/null
@@ -1,170 +0,0 @@
-'use strict';
-
-window.linterConfig.defaults.stylelint = (defaultSeverity => ({
-  // 'sugarss' is a indent-based syntax like Sass or Stylus
-  // ref: https://github.com/postcss/postcss#syntaxes
-  syntax: 'sugarss',
-  // ** recommended rules **
-  // ref: https://github.com/stylelint/stylelint-config-recommended/blob/master/index.js
-  rules: {
-    'at-rule-no-unknown': [true, defaultSeverity],
-    'block-no-empty': [true, defaultSeverity],
-    'color-no-invalid-hex': [true, defaultSeverity],
-    'declaration-block-no-duplicate-properties': [true, {
-      'ignore': ['consecutive-duplicates-with-different-values'],
-      'severity': 'warning'
-    }],
-    'declaration-block-no-shorthand-property-overrides': [true, defaultSeverity],
-    'font-family-no-duplicate-names': [true, defaultSeverity],
-    'function-calc-no-unspaced-operator': [true, defaultSeverity],
-    'function-linear-gradient-no-nonstandard-direction': [true, defaultSeverity],
-    'keyframe-declaration-no-important': [true, defaultSeverity],
-    'media-feature-name-no-unknown': [true, defaultSeverity],
-    /* recommended true */
-    'no-empty-source': false,
-    'no-extra-semicolons': [true, defaultSeverity],
-    'no-invalid-double-slash-comments': [true, defaultSeverity],
-    'property-no-unknown': [true, defaultSeverity],
-    'selector-pseudo-class-no-unknown': [true, defaultSeverity],
-    'selector-pseudo-element-no-unknown': [true, defaultSeverity],
-    'selector-type-no-unknown': false, // for scss/less/stylus-lang
-    'string-no-newline': [true, defaultSeverity],
-    'unit-no-unknown': [true, defaultSeverity],
-
-    // ** non-essential rules
-    'comment-no-empty': false,
-    'declaration-block-no-redundant-longhand-properties': false,
-    'shorthand-property-no-redundant-values': false,
-
-    // ** stylistic rules **
-    /*
-    'at-rule-empty-line-before': [
-      'always',
-      {
-        'except': [
-          'blockless-after-same-name-blockless',
-          'first-nested'
-        ],
-        'ignore': [
-          'after-comment'
-        ]
-      }
-    ],
-    'at-rule-name-case': 'lower',
-    'at-rule-name-space-after': 'always-single-line',
-    'at-rule-semicolon-newline-after': 'always',
-    'block-closing-brace-empty-line-before': 'never',
-    'block-closing-brace-newline-after': 'always',
-    'block-closing-brace-newline-before': 'always-multi-line',
-    'block-closing-brace-space-before': 'always-single-line',
-    'block-opening-brace-newline-after': 'always-multi-line',
-    'block-opening-brace-space-after': 'always-single-line',
-    'block-opening-brace-space-before': 'always',
-    'color-hex-case': 'lower',
-    'color-hex-length': 'short',
-    'comment-empty-line-before': [
-      'always',
-      {
-        'except': [
-          'first-nested'
-        ],
-        'ignore': [
-          'stylelint-commands'
-        ]
-      }
-    ],
-    'comment-whitespace-inside': 'always',
-    'custom-property-empty-line-before': [
-      'always',
-      {
-        'except': [
-          'after-custom-property',
-          'first-nested'
-        ],
-        'ignore': [
-          'after-comment',
-          'inside-single-line-block'
-        ]
-      }
-    ],
-    'declaration-bang-space-after': 'never',
-    'declaration-bang-space-before': 'always',
-    'declaration-block-semicolon-newline-after': 'always-multi-line',
-    'declaration-block-semicolon-space-after': 'always-single-line',
-    'declaration-block-semicolon-space-before': 'never',
-    'declaration-block-single-line-max-declarations': 1,
-    'declaration-block-trailing-semicolon': 'always',
-    'declaration-colon-newline-after': 'always-multi-line',
-    'declaration-colon-space-after': 'always-single-line',
-    'declaration-colon-space-before': 'never',
-    'declaration-empty-line-before': [
-      'always',
-      {
-        'except': [
-          'after-declaration',
-          'first-nested'
-        ],
-        'ignore': [
-          'after-comment',
-          'inside-single-line-block'
-        ]
-      }
-    ],
-    'function-comma-newline-after': 'always-multi-line',
-    'function-comma-space-after': 'always-single-line',
-    'function-comma-space-before': 'never',
-    'function-max-empty-lines': 0,
-    'function-name-case': 'lower',
-    'function-parentheses-newline-inside': 'always-multi-line',
-    'function-parentheses-space-inside': 'never-single-line',
-    'function-whitespace-after': 'always',
-    'indentation': 2,
-    'length-zero-no-unit': true,
-    'max-empty-lines': 1,
-    'media-feature-colon-space-after': 'always',
-    'media-feature-colon-space-before': 'never',
-    'media-feature-name-case': 'lower',
-    'media-feature-parentheses-space-inside': 'never',
-    'media-feature-range-operator-space-after': 'always',
-    'media-feature-range-operator-space-before': 'always',
-    'media-query-list-comma-newline-after': 'always-multi-line',
-    'media-query-list-comma-space-after': 'always-single-line',
-    'media-query-list-comma-space-before': 'never',
-    'no-eol-whitespace': true,
-    'no-missing-end-of-source-newline': true,
-    'number-leading-zero': 'always',
-    'number-no-trailing-zeros': true,
-    'property-case': 'lower',
-    'rule-empty-line-before': [
-      'always-multi-line',
-      {
-        'except': [
-          'first-nested'
-        ],
-        'ignore': [
-          'after-comment'
-        ]
-      }
-    ],
-    'selector-attribute-brackets-space-inside': 'never',
-    'selector-attribute-operator-space-after': 'never',
-    'selector-attribute-operator-space-before': 'never',
-    'selector-combinator-space-after': 'always',
-    'selector-combinator-space-before': 'always',
-    'selector-descendant-combinator-no-non-space': true,
-    'selector-list-comma-newline-after': 'always',
-    'selector-list-comma-space-before': 'never',
-    'selector-max-empty-lines': 0,
-    'selector-pseudo-class-case': 'lower',
-    'selector-pseudo-class-parentheses-space-inside': 'never',
-    'selector-pseudo-element-case': 'lower',
-    'selector-pseudo-element-colon-notation': 'double',
-    'selector-type-case': 'lower',
-    'unit-case': 'lower',
-    'value-list-comma-newline-after': 'always-multi-line',
-    'value-list-comma-space-after': 'always-single-line',
-    'value-list-comma-space-before': 'never',
-    'value-list-max-empty-lines': 0
-    */
-  }
-}))({severity: 'warning'});
diff --git a/edit/lint.js b/edit/lint.js
deleted file mode 100644
index a2c8d71f..00000000
--- a/edit/lint.js
+++ /dev/null
@@ -1,558 +0,0 @@
-/* global CodeMirror messageBox */
-/* global editors makeSectionVisible showCodeMirrorPopup showHelp */
-/* global loadScript require CSSLint stylelint */
-/* global clipString */
-'use strict';
-
-onDOMready().then(loadLinterAssets);
-
-// eslint-disable-next-line no-var
-var linterConfig = {
-  csslint: {},
-  stylelint: {},
-  defaults: {
-    // set in lint-defaults-csslint.js
-    csslint: {},
-    // set in lint-defaults-stylelint.js
-    stylelint: {},
-  },
-  storageName: {
-    csslint: 'editorCSSLintConfig',
-    stylelint: 'editorStylelintConfig',
-  },
-  worker: {
-    csslint: {path: '/edit/csslint-loader.js'},
-    stylelint: {path: '/edit/stylelint-loader.js'},
-  },
-  allRuleIds: {
-    csslint: null,
-    stylelint: null,
-  },
-
-  getName() {
-    // some dirty hacks to override editor.linter getting from prefs
-    const linter = prefs.get('editor.linter');
-    const mode = linter && editors[0] && editors[0].doc.mode;
-    return mode && ((mode.name || mode) !== 'css' || mode.helperType) ? 'stylelint' : linter;
-  },
-
-  getCurrent(linter = linterConfig.getName()) {
-    return this.fallbackToDefaults(this[linter] || {});
-  },
-
-  getForCodeMirror(linter = linterConfig.getName()) {
-    return CodeMirror.lint && CodeMirror.lint[linter] ? {
-      getAnnotations: CodeMirror.lint[linter],
-      delay: prefs.get('editor.lintDelay'),
-      onUpdateLinting(annotationsNotSorted, annotations, cm) {
-        updateLintReport(cm);
-      },
-    } : false;
-  },
-
-  fallbackToDefaults(config, linter = linterConfig.getName()) {
-    if (config && Object.keys(config).length) {
-      if (linter === 'stylelint') {
-        // always use default syntax because we don't expose it in config UI
-        config.syntax = this.defaults.stylelint.syntax;
-      }
-      return Object.assign({}, this.defaults[linter] || {}, config);
-    } else {
-      return deepCopy(this.defaults[linter] || {});
-    }
-  },
-
-  setLinter(linter = linterConfig.getName()) {
-    linter = linter.toLowerCase();
-    linter = linter === 'csslint' || linter === 'stylelint' ? linter : '';
-    if (linterConfig.getName() !== linter) {
-      prefs.set('editor.linter', linter);
-    }
-    return linter;
-  },
-
-  invokeWorker(message) {
-    const worker = linterConfig.worker[message.linter || linterConfig.getName()];
-    if (!worker.queue) {
-      worker.queue = [];
-      worker.instance.onmessage = ({data}) => {
-        worker.queue.shift().resolve(data);
-        if (worker.queue.length) {
-          worker.instance.postMessage(worker.queue[0].message);
-        }
-      };
-    }
-    return new Promise(resolve => {
-      worker.queue.push({message, resolve});
-      if (worker.queue.length === 1) {
-        worker.instance.postMessage(message);
-      }
-    });
-  },
-
-  getAllRuleIds(linter = linterConfig.getName()) {
-    return Promise.resolve(
-      this.allRuleIds[linter] ||
-      this.invokeWorker({linter, action: 'getAllRuleIds'})
-        .then(ids => (this.allRuleIds[linter] = ids.sort()))
-    );
-  },
-
-  findInvalidRules(config, linter = linterConfig.getName()) {
-    return this.getAllRuleIds(linter).then(allRuleIds => {
-      const allRuleIdsSet = new Set(allRuleIds);
-      const rules = linter === 'stylelint' ? config.rules : config;
-      return Object.keys(rules).filter(rule => !allRuleIdsSet.has(rule));
-    });
-  },
-
-  stringify(config = this.getCurrent()) {
-    if (linterConfig.getName() === 'stylelint') {
-      config.syntax = undefined;
-    }
-    return JSON.stringify(config, null, 2)
-      .replace(/,\n\s+\{\n\s+("severity":\s"\w+")\n\s+\}/g, ', {$1}');
-  },
-
-  save(config) {
-    config = this.fallbackToDefaults(config);
-    const linter = linterConfig.getName();
-    this[linter] = config;
-    chromeSync.setLZValue(this.storageName[linter], config);
-    return config;
-  },
-
-  loadAll() {
-    return chromeSync.getLZValues([
-      'editorCSSLintConfig',
-      'editorStylelintConfig',
-    ]).then(data => {
-      this.csslint = this.fallbackToDefaults(data.editorCSSLintConfig, 'csslint');
-      this.stylelint = this.fallbackToDefaults(data.editorStylelintConfig, 'stylelint');
-    });
-  },
-
-  watchStorage() {
-    chrome.storage.onChanged.addListener((changes, area) => {
-      if (area === 'sync') {
-        for (const name of ['editorCSSLintConfig', 'editorStylelintConfig']) {
-          if (name in changes && changes[name].newValue !== changes[name].oldValue) {
-            this.loadAll().then(updateLinter);
-            break;
-          }
-        }
-      }
-    });
-  },
-
-  // this is an event listener so it can't refer to self via 'this'
-  openOnClick(event) {
-    event.preventDefault();
-    setupLinterPopup(linterConfig.stringify());
-  },
-
-  init() {
-    if (!this.init.pending) this.init.pending = this.loadAll();
-    return this.init.pending;
-  }
-};
-
-function initLint() {
-  $('#lint-help').addEventListener('click', showLintHelp);
-  $('#lint').addEventListener('click', gotoLintIssue);
-  $('#linter-settings').addEventListener('click', linterConfig.openOnClick);
-
-  updateLinter();
-  linterConfig.watchStorage();
-  prefs.subscribe(['editor.linter'], updateLinter);
-}
-
-function updateLinter({immediately, linter = linterConfig.getName()} = {}) {
-  if (!immediately) {
-    debounce(updateLinter, 0, {immediately: true, linter});
-    return;
-  }
-  const GUTTERS_CLASS = 'CodeMirror-lint-markers';
-
-  Promise.all([
-    linterConfig.init(),
-    loadLinterAssets(linter)
-  ]).then(updateEditors);
-  $('#linter-settings').style.display = !linter ? 'none' : 'inline-block';
-  $('#lint').classList.add('hidden');
-
-  function updateEditors() {
-    CodeMirror.defaults.lint = linterConfig.getForCodeMirror(linter);
-    const guttersOption = prepareGuttersOption();
-    editors.forEach(cm => {
-      if (cm.options.lint !== CodeMirror.defaults.lint) {
-        cm.setOption('lint', CodeMirror.defaults.lint);
-      }
-      if (guttersOption) {
-        cm.setOption('guttersOption', guttersOption);
-        updateGutters(cm, guttersOption);
-        cm.refresh();
-      }
-      setTimeout(updateLintReport, 0, cm);
-    });
-  }
-
-  function prepareGuttersOption() {
-    const gutters = CodeMirror.defaults.gutters;
-    const needRefresh = Boolean(linter) !== gutters.includes(GUTTERS_CLASS);
-    if (needRefresh) {
-      if (linter) {
-        gutters.push(GUTTERS_CLASS);
-      } else {
-        gutters.splice(gutters.indexOf(GUTTERS_CLASS), 1);
-      }
-    }
-    return needRefresh && gutters;
-  }
-
-  function updateGutters(cm, guttersOption) {
-    cm.options.gutters = guttersOption;
-    const el = $('.' + GUTTERS_CLASS, cm.display.gutters);
-    if (linter && !el) {
-      cm.display.gutters.appendChild($create('.CodeMirror-gutter ' + GUTTERS_CLASS));
-    } else if (!linter && el) {
-      el.remove();
-    }
-  }
-}
-
-function updateLintReport(cm, delay) {
-  const state = cm && cm.state && cm.state.lint || {};
-  if (delay === 0) {
-    // immediately show pending csslint/stylelint messages in onbeforeunload and save
-    clearTimeout(state.lintTimeout);
-    updateLintReportInternal(cm);
-    return;
-  }
-  if (delay > 0) {
-    clearTimeout(state.lintTimeout);
-    state.lintTimeout = setTimeout(cm => {
-      if (cm.performLint) {
-        cm.performLint();
-        updateLintReportInternal(cm);
-      }
-    }, delay, cm);
-    return;
-  }
-  if (state.options) {
-    clearTimeout(state.reportTimeout);
-    const delay = cm && cm.state.renderLintReportNow ? 0 : state.options.delay + 100;
-    state.reportTimeout = setTimeout(updateLintReportInternal, delay, cm, {
-      postponeNewIssues: delay === undefined || delay === null
-    });
-  }
-}
-
-function updateLintReportInternal(scope, {postponeNewIssues} = {}) {
-  const {changed, fixedSome} = (scope ? [scope] : editors).reduce(process, {});
-  if (changed) {
-    const renderNow = editors.last.state.renderLintReportNow =
-      !postponeNewIssues || fixedSome || editors.last.state.renderLintReportNow;
-    debounce(renderLintReport, renderNow ? 0 : CodeMirror.defaults.lintReportDelay, true);
-  }
-
-  function process(result, cm) {
-    const lintState = cm.state.lint || {};
-    const oldMarkers = lintState.stylusMarkers || new Map();
-    const newMarkers = lintState.stylusMarkers = new Map();
-    const oldText = (lintState.body || {}).textContentCached || '';
-    const activeLine = cm.getCursor().line;
-    const body = !(lintState.marked || {}).length ? {} :
-      $create('tbody', lintState.marked.map(mark => {
-        const info = mark.__annotation;
-        const {line, ch} = info.from;
-        const isActiveLine = line === activeLine;
-        const pos = isActiveLine ? 'cursor' : (line + ',' + ch);
-        const title = clipString(info.message, 1000) + `\n(${info.rule})`;
-        const message = clipString(info.message, 100);
-        if (isActiveLine || oldMarkers[pos] === message) {
-          oldMarkers.delete(pos);
-        }
-        newMarkers.set(pos, message);
-        return $create(`tr.${info.severity}`, [
-          $create('td', {attributes: {role: 'severity'}, dataset: {rule: info.rule}},
-            $create('.CodeMirror-lint-marker-' + info.severity, info.severity)),
-          $create('td', {attributes: {role: 'line'}}, line + 1),
-          $create('td', {attributes: {role: 'sep'}}, ':'),
-          $create('td', {attributes: {role: 'col'}}, ch + 1),
-          $create('td', {attributes: {role: 'message'}, title}, message),
-        ]);
-      }));
-    body.textContentCached = body.textContent || '';
-    lintState.body = body.textContentCached && body;
-    result.changed |= oldText !== body.textContentCached;
-    result.fixedSome |= lintState.reportDisplayed && oldMarkers.size;
-    return result;
-  }
-}
-
-function renderLintReport(someBlockChanged) {
-  const container = $('#lint');
-  const content = container.children[1];
-  const label = t('sectionCode');
-  const newContent = content.cloneNode(false);
-  let issueCount = 0;
-  editors.forEach((cm, index) => {
-    cm.state.renderLintReportNow = false;
-    const lintState = cm.state.lint || {};
-    const body = lintState.body;
-    if (!body) {
-      return;
-    }
-    const newBlock = $create('table', {cm}, [
-      $create('caption', label + ' ' + (index + 1)),
-      body,
-    ]);
-    newContent.appendChild(newBlock);
-    issueCount += newBlock.rows.length;
-
-    const block = content.children[newContent.children.length - 1];
-    const blockChanged =
-      !block ||
-      block.cm !== cm ||
-      body.textContentCached !== block.textContentCached;
-    someBlockChanged |= blockChanged;
-    lintState.reportDisplayed = blockChanged;
-  });
-  if (someBlockChanged || newContent.children.length !== content.children.length) {
-    $('#issue-count').textContent = issueCount;
-    container.replaceChild(newContent, content);
-    container.classList.toggle('hidden', !newContent.children.length);
-  }
-}
-
-function gotoLintIssue(event) {
-  const issue = event.target.closest('tr');
-  if (!issue) {
-    return;
-  }
-  const block = issue.closest('table');
-  makeSectionVisible(block.cm);
-  block.cm.focus();
-  block.cm.setSelection({
-    line: parseInt($('td[role="line"]', issue).textContent) - 1,
-    ch: parseInt($('td[role="col"]', issue).textContent) - 1
-  });
-}
-
-function showLintHelp() {
-  const linter = linterConfig.getName();
-  const baseUrl = linter === 'stylelint'
-    ? 'https://stylelint.io/user-guide/rules/'
-    // some CSSLint rules do not have a url
-    : 'https://github.com/CSSLint/csslint/issues/535';
-  let headerLink, template, csslintRules;
-  if (linter === 'csslint') {
-    headerLink = $createLink('https://github.com/CSSLint/csslint/wiki/Rules', 'CSSLint');
-    template = ruleID => {
-      const rule = csslintRules.find(rule => rule.id === ruleID);
-      return rule &&
-        $create('li', [
-          $create('b', $createLink(rule.url || baseUrl, rule.name)),
-          $create('br'),
-          rule.desc,
-        ]);
-    };
-  } else {
-    headerLink = $createLink(baseUrl, 'stylelint');
-    template = rule =>
-      $create('li',
-        rule === 'CssSyntaxError' ? rule : $createLink(baseUrl + rule, rule));
-  }
-  const header = t('linterIssuesHelp', '\x01').split('\x01');
-  const activeRules = new Set($$('#lint td[role="severity"]').map(el => el.dataset.rule));
-  Promise.resolve(linter !== 'csslint' || linterConfig.invokeWorker({action: 'getAllRuleInfos'}))
-    .then(data => {
-      csslintRules = data;
-      showHelp(t('linterIssues'),
-        $create([
-          header[0], headerLink, header[1],
-          $create('ul.rules', [...activeRules.values()].map(template)),
-        ])
-      );
-    });
-}
-
-function showLinterErrorMessage(title, contents, popup) {
-  messageBox({
-    title,
-    contents,
-    className: 'danger center lint-config',
-    buttons: [t('confirmOK')],
-  }).then(() => popup && popup.codebox && popup.codebox.focus());
-}
-
-function setupLinterPopup(config) {
-  const linter = linterConfig.getName();
-  const linterTitle = linter === 'stylelint' ? 'Stylelint' : 'CSSLint';
-  const defaultConfig = linterConfig.stringify(linterConfig.defaults[linter] || {});
-  const title = t('linterConfigPopupTitle', linterTitle);
-  const popup = showCodeMirrorPopup(title, null, {
-    lint: false,
-    extraKeys: {'Ctrl-Enter': save},
-    hintOptions: {hint},
-  });
-  $('.contents', popup).appendChild(makeFooter());
-
-  let cm = popup.codebox;
-  cm.focus();
-  cm.setValue(config);
-  cm.clearHistory();
-  cm.markClean();
-  cm.on('changes', updateButtonState);
-  updateButtonState();
-
-  cm.rerouteHotkeys(false);
-  window.addEventListener('closeHelp', function _() {
-    window.removeEventListener('closeHelp', _);
-    cm.rerouteHotkeys(true);
-    cm = null;
-  });
-
-  loadScript([
-    '/vendor/codemirror/mode/javascript/javascript.js',
-    '/vendor/codemirror/addon/lint/json-lint.js',
-    '/vendor/jsonlint/jsonlint.js'
-  ]).then(() => {
-    cm.setOption('mode', 'application/json');
-    cm.setOption('lint', 'json');
-  });
-
-  function makeFooter() {
-    return $create('div', [
-      $create('p', [
-        $createLink(
-          linter === 'stylelint'
-            ? 'https://stylelint.io/user-guide/rules/'
-            : 'https://github.com/CSSLint/csslint/wiki/Rules-by-ID',
-          t('linterRulesLink')),
-        linter === 'csslint' ? ' ' + t('linterCSSLintSettings') : '',
-      ]),
-      $create('.buttons', [
-        $create('button.save', {onclick: save, title: 'Ctrl-Enter'}, t('styleSaveLabel')),
-        $create('button.cancel', {onclick: cancel}, t('confirmClose')),
-        $create('button.reset', {onclick: reset, title: t('linterResetMessage')}, t('genericResetLabel')),
-      ]),
-    ]);
-  }
-
-  function save(event) {
-    if (event instanceof Event) {
-      event.preventDefault();
-    }
-    const json = tryJSONparse(cm.getValue());
-    if (!json) {
-      showLinterErrorMessage(linter, t('linterJSONError'), popup);
-      cm.focus();
-      return;
-    }
-    linterConfig.findInvalidRules(json, linter).then(invalid => {
-      if (invalid.length) {
-        showLinterErrorMessage(linter, [
-          t('linterInvalidConfigError'),
-          $create('ul', invalid.map(name => $create('li', name))),
-        ], popup);
-        return;
-      }
-      linterConfig.setLinter(linter);
-      linterConfig.save(json);
-      cm.markClean();
-      cm.focus();
-      updateButtonState();
-    });
-  }
-
-  function reset(event) {
-    event.preventDefault();
-    linterConfig.setLinter(linter);
-    cm.setValue(defaultConfig);
-    cm.focus();
-    updateButtonState();
-  }
-
-  function cancel(event) {
-    event.preventDefault();
-    $('.dismiss').dispatchEvent(new Event('click'));
-  }
-
-  function updateButtonState() {
-    $('.save', popup).disabled = cm.isClean();
-    $('.reset', popup).disabled = cm.getValue() === defaultConfig;
-    $('.cancel', popup).textContent = t(cm.isClean() ? 'confirmClose' : 'confirmCancel');
-  }
-
-  function hint(cm) {
-    return Promise.all([
-      linterConfig.getAllRuleIds(linter),
-      linter !== 'stylelint' || hint.allOptions ||
-        linterConfig.invokeWorker({action: 'getAllRuleOptions', linter})
-          .then(options => (hint.allOptions = options)),
-    ])
-    .then(([ruleIds, options]) => {
-      const cursor = cm.getCursor();
-      const {start, end, string, type, state: {lexical}} = cm.getTokenAt(cursor);
-      const {line, ch} = cursor;
-
-      const quoted = string.startsWith('"');
-      const leftPart = string.slice(quoted ? 1 : 0, ch - start).trim();
-      const depth = getLexicalDepth(lexical);
-
-      const search = cm.getSearchCursor(/"([-\w]+)"/, {line, ch: start - 1});
-      let [, prevWord] = search.find(true) || [];
-      let words = [];
-
-      if (depth === 1 && linter === 'stylelint') {
-        words = quoted ? ['rules'] : [];
-      } else if ((depth === 1 || depth === 2) && type && type.includes('property')) {
-        words = ruleIds;
-      } else if (depth === 2 || depth === 3 && lexical.type === ']') {
-        words = !quoted ? ['true', 'false', 'null'] :
-          ruleIds.includes(prevWord) && (options[prevWord] || [])[0] || [];
-      } else if (depth === 4 && prevWord === 'severity') {
-        words = ['error', 'warning'];
-      } else if (depth === 4) {
-        words = ['ignore', 'ignoreAtRules', 'except', 'severity'];
-      } else if (depth === 5 && lexical.type === ']' && quoted) {
-        while (prevWord && !ruleIds.includes(prevWord)) {
-          prevWord = (search.find(true) || [])[1];
-        }
-        words = (options[prevWord] || []).slice(-1)[0] || ruleIds;
-      }
-      return {
-        list: words.filter(word => word.startsWith(leftPart)),
-        from: {line, ch: start + (quoted ? 1 : 0)},
-        to: {line, ch: string.endsWith('"') ? end - 1 : end},
-      };
-    });
-  }
-
-  function getLexicalDepth(lexicalState) {
-    let depth = 0;
-    while ((lexicalState = lexicalState.prev)) {
-      depth++;
-    }
-    return depth;
-  }
-}
-
-function loadLinterAssets(name = linterConfig.getName()) {
-  const worker = linterConfig.worker[name];
-  if (!name || !worker) return Promise.resolve();
-  const scripts = [];
-  if (!worker.instance) {
-    worker.instance = new Worker(worker.path);
-    scripts.push(`/edit/lint-defaults-${name}.js`);
-  }
-  if (!CodeMirror.lint) {
-    scripts.push(
-      '/vendor/codemirror/addon/lint/lint.css',
-      '/vendor/codemirror/addon/lint/lint.js',
-      '/edit/lint-codemirror-helper.js');
-  }
-  return scripts.length ? loadScript(scripts) : Promise.resolve();
-}
diff --git a/edit/linter-config-dialog.js b/edit/linter-config-dialog.js
new file mode 100644
index 00000000..c1ccf51f
--- /dev/null
+++ b/edit/linter-config-dialog.js
@@ -0,0 +1,196 @@
+/* global memoize editorWorker showCodeMirrorPopup loadScript messageBox LINTER_DEFAULTS*/
+'use strict';
+
+(() => {
+  document.addEventListener('DOMContentLoaded', () => {
+    $('#linter-settings').addEventListener('click', showLintConfig);
+  }, {once: true});
+
+  function stringifyConfig(config) {
+    return JSON.stringify(config, null, 2)
+      .replace(/,\n\s+\{\n\s+("severity":\s"\w+")\n\s+\}/g, ', {$1}');
+  }
+
+  function showLinterErrorMessage(title, contents, popup) {
+    messageBox({
+      title,
+      contents,
+      className: 'danger center lint-config',
+      buttons: [t('confirmOK')],
+    }).then(() => popup && popup.codebox && popup.codebox.focus());
+  }
+
+  function showLintConfig() {
+    const linter = $('#editor.linter').value;
+    if (!linter) {
+      return;
+    }
+    const storageName = linter === 'styleint' ? 'editorStylelintConfig' : 'editorCSSLintConfig';
+    const getRules = memoize(linter === 'stylelint' ?
+      editorWorker.getStylelintRules : editorWorker.getCsslintRules);
+    const linterTitle = linter === 'stylelint' ? 'Stylelint' : 'CSSLint';
+    const defaultConfig = stringifyConfig(
+      linter === 'stylelint' ? LINTER_DEFAULTS.STYLELINT : LINTER_DEFAULTS.CSSLINT
+    );
+    const title = t('linterConfigPopupTitle', linterTitle);
+    const popup = showCodeMirrorPopup(title, null, {
+      lint: false,
+      extraKeys: {'Ctrl-Enter': save},
+      hintOptions: {hint},
+    });
+    $('.contents', popup).appendChild(makeFooter());
+
+    let cm = popup.codebox;
+    cm.focus();
+    chromeSync.getLZValue(storageName).then(config => {
+      cm.setValue(config ? stringifyConfig(config) : defaultConfig);
+      cm.clearHistory();
+      cm.markClean();
+      updateButtonState();
+    });
+    cm.on('changes', updateButtonState);
+
+    cm.rerouteHotkeys(false);
+    window.addEventListener('closeHelp', function _() {
+      window.removeEventListener('closeHelp', _);
+      cm.rerouteHotkeys(true);
+      cm = null;
+    });
+
+    loadScript([
+      '/vendor/codemirror/mode/javascript/javascript.js',
+      '/vendor/codemirror/addon/lint/json-lint.js',
+      '/vendor/jsonlint/jsonlint.js'
+    ]).then(() => {
+      cm.setOption('mode', 'application/json');
+      cm.setOption('lint', true);
+    });
+
+    function findInvalidRules(config, linter) {
+      return getRules()
+        .then(rules => {
+          if (linter === 'stylelint') {
+            return Object.keys(config.rules).filter(k => !rules.hasOwnProperty(k));
+          }
+          const ruleSet = new Set(rules.map(r => r.id));
+          return Object.keys(config).filter(k => !ruleSet.has(k));
+        });
+    }
+
+    function makeFooter() {
+      return $create('div', [
+        $create('p', [
+          $createLink(
+            linter === 'stylelint'
+              ? 'https://stylelint.io/user-guide/rules/'
+              : 'https://github.com/CSSLint/csslint/wiki/Rules-by-ID',
+            t('linterRulesLink')),
+          linter === 'csslint' ? ' ' + t('linterCSSLintSettings') : '',
+        ]),
+        $create('.buttons', [
+          $create('button.save', {onclick: save, title: 'Ctrl-Enter'}, t('styleSaveLabel')),
+          $create('button.cancel', {onclick: cancel}, t('confirmClose')),
+          $create('button.reset', {onclick: reset, title: t('linterResetMessage')}, t('genericResetLabel')),
+        ]),
+      ]);
+    }
+
+    function save(event) {
+      if (event instanceof Event) {
+        event.preventDefault();
+      }
+      const json = tryJSONparse(cm.getValue());
+      if (!json) {
+        showLinterErrorMessage(linter, t('linterJSONError'), popup);
+        cm.focus();
+        return;
+      }
+      findInvalidRules(json, linter).then(invalid => {
+        if (invalid.length) {
+          showLinterErrorMessage(linter, [
+            t('linterInvalidConfigError'),
+            $create('ul', invalid.map(name => $create('li', name))),
+          ], popup);
+          return;
+        }
+        chromeSync.setLZValue(storageName, json);
+        cm.markClean();
+        cm.focus();
+        updateButtonState();
+      });
+    }
+
+    function reset(event) {
+      event.preventDefault();
+      cm.setValue(defaultConfig);
+      cm.focus();
+      updateButtonState();
+    }
+
+    function cancel(event) {
+      event.preventDefault();
+      $('.dismiss').dispatchEvent(new Event('click'));
+    }
+
+    function updateButtonState() {
+      $('.save', popup).disabled = cm.isClean();
+      $('.reset', popup).disabled = cm.getValue() === defaultConfig;
+      $('.cancel', popup).textContent = t(cm.isClean() ? 'confirmClose' : 'confirmCancel');
+    }
+
+    function hint(cm) {
+      return getRules().then(rules => {
+        let ruleIds, options;
+        if (linter === 'stylelint') {
+          ruleIds = Object.keys(rules);
+          options = rules;
+        } else {
+          ruleIds = rules.map(r => r.id);
+          options = {};
+        }
+        const cursor = cm.getCursor();
+        const {start, end, string, type, state: {lexical}} = cm.getTokenAt(cursor);
+        const {line, ch} = cursor;
+
+        const quoted = string.startsWith('"');
+        const leftPart = string.slice(quoted ? 1 : 0, ch - start).trim();
+        const depth = getLexicalDepth(lexical);
+
+        const search = cm.getSearchCursor(/"([-\w]+)"/, {line, ch: start - 1});
+        let [, prevWord] = search.find(true) || [];
+        let words = [];
+
+        if (depth === 1 && linter === 'stylelint') {
+          words = quoted ? ['rules'] : [];
+        } else if ((depth === 1 || depth === 2) && type && type.includes('property')) {
+          words = ruleIds;
+        } else if (depth === 2 || depth === 3 && lexical.type === ']') {
+          words = !quoted ? ['true', 'false', 'null'] :
+            ruleIds.includes(prevWord) && (options[prevWord] || [])[0] || [];
+        } else if (depth === 4 && prevWord === 'severity') {
+          words = ['error', 'warning'];
+        } else if (depth === 4) {
+          words = ['ignore', 'ignoreAtRules', 'except', 'severity'];
+        } else if (depth === 5 && lexical.type === ']' && quoted) {
+          while (prevWord && !ruleIds.includes(prevWord)) {
+            prevWord = (search.find(true) || [])[1];
+          }
+          words = (options[prevWord] || []).slice(-1)[0] || ruleIds;
+        }
+        return {
+          list: words.filter(word => word.startsWith(leftPart)),
+          from: {line, ch: start + (quoted ? 1 : 0)},
+          to: {line, ch: string.endsWith('"') ? end - 1 : end},
+        };
+      });
+    }
+
+    function getLexicalDepth(lexicalState) {
+      let depth = 0;
+      while ((lexicalState = lexicalState.prev)) {
+        depth++;
+      }
+      return depth;
+    }
+  }
+})();
diff --git a/edit/linter-defaults.js b/edit/linter-defaults.js
new file mode 100644
index 00000000..e02e5420
--- /dev/null
+++ b/edit/linter-defaults.js
@@ -0,0 +1,219 @@
+'use strict';
+
+// eslint-disable-next-line no-var
+var LINTER_DEFAULTS = (() => {
+  const SEVERITY = {severity: 'warning'};
+  const STYLELINT = {
+    // 'sugarss' is a indent-based syntax like Sass or Stylus
+    // ref: https://github.com/postcss/postcss#syntaxes
+    // syntax: 'sugarss',
+    // ** recommended rules **
+    // ref: https://github.com/stylelint/stylelint-config-recommended/blob/master/index.js
+    rules: {
+      'at-rule-no-unknown': [true, SEVERITY],
+      'block-no-empty': [true, SEVERITY],
+      'color-no-invalid-hex': [true, SEVERITY],
+      'declaration-block-no-duplicate-properties': [true, {
+        'ignore': ['consecutive-duplicates-with-different-values'],
+        'severity': 'warning'
+      }],
+      'declaration-block-no-shorthand-property-overrides': [true, SEVERITY],
+      'font-family-no-duplicate-names': [true, SEVERITY],
+      'function-calc-no-unspaced-operator': [true, SEVERITY],
+      'function-linear-gradient-no-nonstandard-direction': [true, SEVERITY],
+      'keyframe-declaration-no-important': [true, SEVERITY],
+      'media-feature-name-no-unknown': [true, SEVERITY],
+      /* recommended true */
+      'no-empty-source': false,
+      'no-extra-semicolons': [true, SEVERITY],
+      'no-invalid-double-slash-comments': [true, SEVERITY],
+      'property-no-unknown': [true, SEVERITY],
+      'selector-pseudo-class-no-unknown': [true, SEVERITY],
+      'selector-pseudo-element-no-unknown': [true, SEVERITY],
+      'selector-type-no-unknown': false, // for scss/less/stylus-lang
+      'string-no-newline': [true, SEVERITY],
+      'unit-no-unknown': [true, SEVERITY],
+
+      // ** non-essential rules
+      'comment-no-empty': false,
+      'declaration-block-no-redundant-longhand-properties': false,
+      'shorthand-property-no-redundant-values': false,
+
+      // ** stylistic rules **
+      /*
+      'at-rule-empty-line-before': [
+        'always',
+        {
+          'except': [
+            'blockless-after-same-name-blockless',
+            'first-nested'
+          ],
+          'ignore': [
+            'after-comment'
+          ]
+        }
+      ],
+      'at-rule-name-case': 'lower',
+      'at-rule-name-space-after': 'always-single-line',
+      'at-rule-semicolon-newline-after': 'always',
+      'block-closing-brace-empty-line-before': 'never',
+      'block-closing-brace-newline-after': 'always',
+      'block-closing-brace-newline-before': 'always-multi-line',
+      'block-closing-brace-space-before': 'always-single-line',
+      'block-opening-brace-newline-after': 'always-multi-line',
+      'block-opening-brace-space-after': 'always-single-line',
+      'block-opening-brace-space-before': 'always',
+      'color-hex-case': 'lower',
+      'color-hex-length': 'short',
+      'comment-empty-line-before': [
+        'always',
+        {
+          'except': [
+            'first-nested'
+          ],
+          'ignore': [
+            'stylelint-commands'
+          ]
+        }
+      ],
+      'comment-whitespace-inside': 'always',
+      'custom-property-empty-line-before': [
+        'always',
+        {
+          'except': [
+            'after-custom-property',
+            'first-nested'
+          ],
+          'ignore': [
+            'after-comment',
+            'inside-single-line-block'
+          ]
+        }
+      ],
+      'declaration-bang-space-after': 'never',
+      'declaration-bang-space-before': 'always',
+      'declaration-block-semicolon-newline-after': 'always-multi-line',
+      'declaration-block-semicolon-space-after': 'always-single-line',
+      'declaration-block-semicolon-space-before': 'never',
+      'declaration-block-single-line-max-declarations': 1,
+      'declaration-block-trailing-semicolon': 'always',
+      'declaration-colon-newline-after': 'always-multi-line',
+      'declaration-colon-space-after': 'always-single-line',
+      'declaration-colon-space-before': 'never',
+      'declaration-empty-line-before': [
+        'always',
+        {
+          'except': [
+            'after-declaration',
+            'first-nested'
+          ],
+          'ignore': [
+            'after-comment',
+            'inside-single-line-block'
+          ]
+        }
+      ],
+      'function-comma-newline-after': 'always-multi-line',
+      'function-comma-space-after': 'always-single-line',
+      'function-comma-space-before': 'never',
+      'function-max-empty-lines': 0,
+      'function-name-case': 'lower',
+      'function-parentheses-newline-inside': 'always-multi-line',
+      'function-parentheses-space-inside': 'never-single-line',
+      'function-whitespace-after': 'always',
+      'indentation': 2,
+      'length-zero-no-unit': true,
+      'max-empty-lines': 1,
+      'media-feature-colon-space-after': 'always',
+      'media-feature-colon-space-before': 'never',
+      'media-feature-name-case': 'lower',
+      'media-feature-parentheses-space-inside': 'never',
+      'media-feature-range-operator-space-after': 'always',
+      'media-feature-range-operator-space-before': 'always',
+      'media-query-list-comma-newline-after': 'always-multi-line',
+      'media-query-list-comma-space-after': 'always-single-line',
+      'media-query-list-comma-space-before': 'never',
+      'no-eol-whitespace': true,
+      'no-missing-end-of-source-newline': true,
+      'number-leading-zero': 'always',
+      'number-no-trailing-zeros': true,
+      'property-case': 'lower',
+      'rule-empty-line-before': [
+        'always-multi-line',
+        {
+          'except': [
+            'first-nested'
+          ],
+          'ignore': [
+            'after-comment'
+          ]
+        }
+      ],
+      'selector-attribute-brackets-space-inside': 'never',
+      'selector-attribute-operator-space-after': 'never',
+      'selector-attribute-operator-space-before': 'never',
+      'selector-combinator-space-after': 'always',
+      'selector-combinator-space-before': 'always',
+      'selector-descendant-combinator-no-non-space': true,
+      'selector-list-comma-newline-after': 'always',
+      'selector-list-comma-space-before': 'never',
+      'selector-max-empty-lines': 0,
+      'selector-pseudo-class-case': 'lower',
+      'selector-pseudo-class-parentheses-space-inside': 'never',
+      'selector-pseudo-element-case': 'lower',
+      'selector-pseudo-element-colon-notation': 'double',
+      'selector-type-case': 'lower',
+      'unit-case': 'lower',
+      'value-list-comma-newline-after': 'always-multi-line',
+      'value-list-comma-space-after': 'always-single-line',
+      'value-list-comma-space-before': 'never',
+      'value-list-max-empty-lines': 0
+      */
+    }
+  };
+  const CSSLINT = {
+    // Default warnings
+    'display-property-grouping': 1,
+    'duplicate-properties': 1,
+    'empty-rules': 1,
+    'errors': 1,
+    'warnings': 1,
+    'known-properties': 1,
+
+    // Default disabled
+    'adjoining-classes': 0,
+    'box-model': 0,
+    'box-sizing': 0,
+    'bulletproof-font-face': 0,
+    'compatible-vendor-prefixes': 0,
+    'duplicate-background-images': 0,
+    'fallback-colors': 0,
+    'floats': 0,
+    'font-faces': 0,
+    'font-sizes': 0,
+    'gradients': 0,
+    'ids': 0,
+    'import': 0,
+    'import-ie-limit': 0,
+    'important': 0,
+    'order-alphabetical': 0,
+    'outline-none': 0,
+    'overqualified-elements': 0,
+    'qualified-headings': 0,
+    'regex-selectors': 0,
+    'rules-count': 0,
+    'selector-max': 0,
+    'selector-max-approaching': 0,
+    'selector-newline': 0,
+    'shorthand': 0,
+    'star-property-hack': 0,
+    'text-indent': 0,
+    'underscore-property-hack': 0,
+    'unique-headings': 0,
+    'universal-selector': 0,
+    'unqualified-attributes': 0,
+    'vendor-prefix': 0,
+    'zero-units': 0
+  };
+  return {STYLELINT, CSSLINT, SEVERITY};
+})();
diff --git a/edit/linter-engines.js b/edit/linter-engines.js
new file mode 100644
index 00000000..f884ceda
--- /dev/null
+++ b/edit/linter-engines.js
@@ -0,0 +1,113 @@
+/* global LINTER_DEFAULTS linter editorWorker */
+'use strict';
+
+(() => {
+  registerLinters({
+    csslint: {
+      storageName: 'editorCSSLintConfig',
+      lint: csslint,
+      validMode: mode => mode === 'css',
+      getConfig: config => Object.assign({}, LINTER_DEFAULTS.CSSLINT, config)
+    },
+    stylelint: {
+      storageName: 'editorStylelintConfig',
+      lint: stylelint,
+      validMode: () => true,
+      getConfig: config => ({
+        syntax: 'sugarss',
+        rules: Object.assign({}, LINTER_DEFAULTS.STYLELINT.rules, config && config.rules)
+      })
+    }
+  });
+
+  function stylelint(text, config, mode) {
+    return editorWorker.stylelint(text, config)
+      .then(({results}) => {
+        if (!results[0]) {
+          return [];
+        }
+        const output = results[0].warnings.map(({line, column: ch, text, severity}) =>
+          ({
+            from: {line: line - 1, ch: ch - 1},
+            to: {line: line - 1, ch},
+            message: text
+              .replace('Unexpected ', '')
+              .replace(/^./, firstLetter => firstLetter.toUpperCase())
+              .replace(/\s*\([^(]+\)$/, ''), // strip the rule,
+            rule: text.replace(/^.*?\s*\(([^(]+)\)$/, '$1'),
+            severity,
+          })
+        );
+        return mode !== 'stylus' ?
+          output :
+          output.filter(({message}) =>
+            !message.includes('"@css"') || !message.includes('(at-rule-no-unknown)'));
+      });
+  }
+
+  function csslint(text, config) {
+    return editorWorker.csslint(text, config)
+      .then(results =>
+        results
+          .map(({line, col: ch, message, rule, type: severity}) => line && {
+            message,
+            from: {line: line - 1, ch: ch - 1},
+            to: {line: line - 1, ch},
+            rule: rule.id,
+            severity,
+          })
+          .filter(Boolean)
+      );
+  }
+
+  function registerLinters(engines) {
+    const configs = new Map();
+
+    chrome.storage.onChanged.addListener((changes, area) => {
+      if (area !== 'sync') {
+        return;
+      }
+      for (const [name, engine] of Object.entries(engines)) {
+        if (changes.hasOwnProperty(engine.storageName)) {
+          chromeSync.getLZValue(engine.storageName)
+            .then(config => {
+              configs.set(name, engine.getConfig(config));
+              linter.run();
+            });
+        }
+      }
+    });
+
+    linter.register((text, options, cm) => {
+      const selectedLinter = prefs.get('editor.linter');
+      if (!selectedLinter) {
+        return;
+      }
+      const mode = cm.getOption('mode');
+      if (engines[selectedLinter].validMode(mode)) {
+        return runLint(selectedLinter);
+      }
+      for (const [name, engine] of Object.entries(engines)) {
+        if (engine.validMode(mode)) {
+          return runLint(name);
+        }
+      }
+
+      function runLint(name) {
+        return getConfig(name)
+          .then(config => engines[name].lint(text, config, mode));
+      }
+    });
+
+    function getConfig(name) {
+      if (configs.has(name)) {
+        return Promise.resolve(configs.get(name));
+      }
+      return chromeSync.getLZValue(engines[name].storageName)
+        .then(config => {
+          configs.set(name, engines[name].getConfig(config));
+          return configs.get(name);
+        });
+    }
+  }
+})();
diff --git a/edit/linter-help-dialog.js b/edit/linter-help-dialog.js
new file mode 100644
index 00000000..7946a6e5
--- /dev/null
+++ b/edit/linter-help-dialog.js
@@ -0,0 +1,51 @@
+/* global showHelp editorWorker memoize */
+'use strict';
+
+function createLinterHelpDialog(getIssues) {
+  let csslintRules;
+  const prepareCsslintRules = memoize(() =>
+    editorWorker.getCsslintRules()
+      .then(rules => {
+        csslintRules = rules;
+      })
+  );
+  return {show};
+
+  function show() {
+    // FIXME: implement a linterChooser?
+    const linter = $('#editor.linter').value;
+    const baseUrl = linter === 'stylelint'
+      ? 'https://stylelint.io/user-guide/rules/'
+      // some CSSLint rules do not have a url
+      : 'https://github.com/CSSLint/csslint/issues/535';
+    let headerLink, template;
+    if (linter === 'csslint') {
+      headerLink = $createLink('https://github.com/CSSLint/csslint/wiki/Rules', 'CSSLint');
+      template = ({rule: ruleID}) => {
+        const rule = csslintRules.find(rule => rule.id === ruleID);
+        return rule &&
+          $create('li', [
+            $create('b', $createLink(rule.url || baseUrl, rule.name)),
+            $create('br'),
+            rule.desc,
+          ]);
+      };
+    } else {
+      headerLink = $createLink(baseUrl, 'stylelint');
+      template = ({rule}) =>
+        $create('li',
+          rule === 'CssSyntaxError' ? rule : $createLink(baseUrl + rule, rule));
+    }
+    const header = t('linterIssuesHelp', '\x01').split('\x01');
+    const activeRules = getIssues();
+    Promise.resolve(linter === 'csslint' && prepareCsslintRules())
+      .then(() =>
+        showHelp(t('linterIssues'),
+          $create([
+            header[0], headerLink, header[1],
+            $create('ul.rules', [...activeRules.values()].map(template)),
+          ])
+        )
+      );
+  }
+}
diff --git a/edit/linter-meta.js b/edit/linter-meta.js
new file mode 100644
index 00000000..4233c402
--- /dev/null
+++ b/edit/linter-meta.js
@@ -0,0 +1,47 @@
+/* global linter */
+'use strict';
+
+function createMetaCompiler(cm) {
+  const updateListeners = [];
+  let meta = null;
+  let metaIndex = null;
+  let cache = [];
+
+  linter.register((text, options, _cm) => {
+    if (_cm !== cm) {
+      return;
+    }
+    const match = text.match(/\/\*\s*==userstyle==[\s\S]*?==\/userstyle==\s*\*\//i);
+    if (!match) {
+      return [];
+    }
+    if (match[0] === meta && match.index === metaIndex) {
+      return cache;
+    }
+    return API.parseUsercss({sourceCode: match[0], metaOnly: true})
+      .then(result => result.usercssData)
+      .then(result => {
+        for (const cb of updateListeners) {
+          cb(result);
+        }
+        meta = match[0];
+        metaIndex = match.index;
+        cache = [];
+        return cache;
+      }, err => {
+        meta = match[0];
+        metaIndex = match.index;
+        cache = [{
+          from: cm.posFromIndex((err.index || 0) + match.index),
+          to: cm.posFromIndex((err.index || 0) + match.index),
+          message: err.message,
+          severity: 'error'
+        }];
+        return cache;
+      });
+  });
+
+  return {
+    onUpdated: cb => updateListeners.push(cb)
+  };
+}
diff --git a/edit/linter-report.js b/edit/linter-report.js
new file mode 100644
index 00000000..d12df230
--- /dev/null
+++ b/edit/linter-report.js
@@ -0,0 +1,165 @@
+/* global linter editors clipString createLinterHelpDialog makeSectionVisible */
+'use strict';
+
+// eslint-disable-next-line no-var
+Object.assign(linter, (() => {
+  const tables = new Map();
+  const helpDialog = createLinterHelpDialog(getIssues);
+
+  document.addEventListener('DOMContentLoaded', () => {
+    $('#lint-help').addEventListener('click', helpDialog.show);
+  }, {once: true});
+
+  linter.onLintingUpdated((annotationsNotSorted, annotations, cm) => {
+    let table = tables.get(cm);
+    if (!table) {
+      table = createTable(cm);
+      tables.set(cm, table);
+      const container = $('.lint-report-container');
+      if (typeof editor === 'object') {
+        container.append(table.element);
+      } else {
+        const nextSibling = findNextSibling(tables, cm);
+        container.insertBefore(table.element, nextSibling && tables.get(nextSibling).element);
+      }
+    }
+    table.updateCaption();
+    table.updateAnnotations(annotations);
+    updateCount();
+  });
+
+  linter.onUnhook(cm => {
+    const table = tables.get(cm);
+    if (table) {
+      table.element.remove();
+      tables.delete(cm);
+    }
+    updateCount();
+  });
+
+  return {refreshReport};
+
+  function updateCount() {
+    const issueCount = Array.from(tables.values())
+      .reduce((sum, table) => sum + table.trs.length, 0);
+    $('#lint').classList.toggle('hidden', issueCount === 0);
+    $('#issue-count').textContent = issueCount;
+  }
+
+  function getIssues() {
+    const issues = new Set();
+    for (const table of tables.values()) {
+      for (const tr of table.trs) {
+        issues.add(tr.getAnnotation());
+      }
+    }
+    return issues;
+  }
+
+  function findNextSibling(tables, cm) {
+    let i = editors.indexOf(cm) + 1;
+    while (i < editors.length) {
+      if (tables.has(editors[i])) {
+        return editors[i];
+      }
+      i++;
+    }
+  }
+
+  function refreshReport() {
+    for (const table of tables.values()) {
+      table.updateCaption();
+    }
+  }
+
+  function createTable(cm) {
+    const caption = $create('caption');
+    const tbody = $create('tbody');
+    const table = $create('table', [caption, tbody]);
+    const trs = [];
+    return {
+      element: table,
+      trs,
+      updateAnnotations,
+      updateCaption
+    };
+
+    function updateCaption() {
+      caption.textContent = typeof editor === 'object' ?
+        '' : `${t('sectionCode')} ${editors.indexOf(cm) + 1}`;
+    }
+
+    function updateAnnotations(lines) {
+      let i = 0;
+      for (const anno of getAnnotations()) {
+        let tr;
+        if (i < trs.length) {
+          tr = trs[i];
+        } else {
+          tr = createTr();
+          trs.push(tr);
+          tbody.append(tr.element);
+        }
+        tr.update(anno);
+        i++;
+      }
+      if (i === 0) {
+        trs.length = 0;
+        tbody.textContent = '';
+      } else {
+        while (trs.length > i) {
+          trs.pop().element.remove();
+        }
+      }
+      table.classList.toggle('empty', trs.length === 0);
+
+      function *getAnnotations() {
+        for (const line of lines.filter(Boolean)) {
+          yield *line;
+        }
+      }
+    }
+
+    function createTr() {
+      let anno;
+      const severityIcon = $create('div');
+      const severity = $create('td', {attributes: {role: 'severity'}}, severityIcon);
+      const line = $create('td', {attributes: {role: 'line'}});
+      const col = $create('td', {attributes: {role: 'col'}});
+      const message = $create('td', {attributes: {role: 'message'}});
+
+      const trElement = $create('tr', {
+        onclick: () => gotoLintIssue(cm, anno)
+      }, [
+        severity,
+        line,
+        $create('td', {attributes: {role: 'sep'}}, ':'),
+        col,
+        message
+      ]);
+      return {
+        element: trElement,
+        update,
+        getAnnotation: () => anno
+      };
+
+      function update(_anno) {
+        anno = _anno;
+        trElement.className = anno.severity;
+        severity.dataset.rule = anno.rule;
+        severityIcon.className = `CodeMirror-lint-marker-${anno.severity}`;
+        severityIcon.textContent = anno.severity;
+        line.textContent = anno.from.line + 1;
+        col.textContent = anno.from.ch + 1;
+        message.title = clipString(anno.message, 1000) + `\n(${anno.rule})`;
+        message.textContent = clipString(anno.message, 100);
+      }
+    }
+  }
+
+  function gotoLintIssue(cm, anno) {
+    makeSectionVisible(cm);
+    cm.focus();
+    cm.setSelection(anno.from);
+  }
+})());
diff --git a/edit/linter.js b/edit/linter.js
new file mode 100644
index 00000000..5cb7f779
--- /dev/null
+++ b/edit/linter.js
@@ -0,0 +1,65 @@
+'use strict';
+
+// eslint-disable-next-line no-var
+var linter = (() => {
+  const lintingUpdatedListeners = [];
+  const unhookListeners = [];
+  const linters = [];
+  const cms = new Set();
+
+  return {
+    register,
+    run,
+    enableForEditor,
+    disableForEditor,
+    onLintingUpdated,
+    onUnhook
+  };
+
+  function onUnhook(cb) {
+    unhookListeners.push(cb);
+  }
+
+  function onLintingUpdated(cb) {
+    lintingUpdatedListeners.push(cb);
+  }
+
+  function onUpdateLinting(...args) {
+    for (const cb of lintingUpdatedListeners) {
+      cb(...args);
+    }
+  }
+
+  function enableForEditor(cm) {
+    cm.setOption('lint', {onUpdateLinting, getAnnotations});
+    cms.add(cm);
+  }
+
+  function disableForEditor(cm) {
+    cm.setOption('lint', false);
+    cms.delete(cm);
+    for (const cb of unhookListeners) {
+      cb(cm);
+    }
+  }
+
+  function register(linterFn) {
+    linters.push(linterFn);
+  }
+
+  function run() {
+    for (const cm of cms) {
+      cm.performLint();
+    }
+  }
+
+  function getAnnotations(...args) {
+    return Promise.all(linters.map(fn => fn(...args)))
+      .then(results => [].concat(...results.filter(Boolean)));
+  }
+})();
+
+// FIXME: this should be put inside edit.js
+prefs.subscribe(['editor.linter'], () => {
+  linter.run();
+});
diff --git a/edit/sections.js b/edit/sections.js
index 1a2cb5ac..44ef3a50 100644
--- a/edit/sections.js
+++ b/edit/sections.js
@@ -1,11 +1,11 @@
 /*
 global CodeMirror
 global editors propertyToCss CssToProperty
-global onChange indicateCodeChange initHooks setCleanGlobal
+global onChange initHooks setCleanGlobal
 global fromMozillaFormat maximizeCodeHeight toggleContextMenuDelete
-global setCleanItem updateTitle updateLintReportIfEnabled renderLintReport
+global setCleanItem updateTitle
 global showAppliesToHelp beautify regExpTester setGlobalProgress setCleanSection
-global clipString
+global clipString linter
 */
 'use strict';
 
@@ -146,12 +146,13 @@ function addSection(event, section) {
     const newIndex = getSections().indexOf(clickedSection) + 1;
     cm = setupCodeMirror(div, code, newIndex);
     makeSectionVisible(cm);
-    renderLintReport();
     cm.focus();
   } else {
     sections.appendChild(div);
     cm = setupCodeMirror(div, code);
   }
+  linter.enableForEditor(cm);
+  linter.refreshReport();
   div.CodeMirror = cm;
   setCleanSection(div);
   return div;
@@ -308,7 +309,6 @@ function indicateCodeChange(cm) {
   const section = cm.getSection();
   setCleanItem(section, cm.isClean(section.savedValue));
   updateTitle();
-  updateLintReportIfEnabled(cm);
 }
 
 function setupAutocomplete(cm, enable = true) {
@@ -481,13 +481,16 @@ function removeSection(event) {
       setCleanItem(section, false);
       updateTitle();
       cm.focus();
+      linter.enableForEditor(cm);
+      linter.refreshReport();
     };
     section.insertAdjacentElement('afterend', stub);
   }
   setCleanItem($('#sections'), false);
   removeAreaAndSetDirty(section);
   editors.splice(editors.indexOf(cm), 1);
-  renderLintReport();
+  linter.disableForEditor(cm);
+  linter.refreshReport();
 }
 
 function removeAreaAndSetDirty(area) {
diff --git a/edit/source-editor.js b/edit/source-editor.js
index e14f74a9..3a5d6c32 100644
--- a/edit/source-editor.js
+++ b/edit/source-editor.js
@@ -1,10 +1,10 @@
 /*
 global editors styleId: true
 global CodeMirror dirtyReporter
-global updateLintReportIfEnabled initLint linterConfig updateLinter
 global createAppliesToLineWidget messageBox
 global sectionsToMozFormat
 global beforeUnload
+global createMetaCompiler linter
 */
 'use strict';
 
@@ -44,7 +44,6 @@ function createSourceEditor(style) {
 
   cm.on('changes', () => {
     dirty.modify('sourceGeneration', savedGeneration, cm.changeGeneration());
-    updateLintReportIfEnabled(cm);
   });
 
   CodeMirror.commands.prevEditor = cm => nextPrevMozDocument(cm, -1);
@@ -55,9 +54,17 @@ function createSourceEditor(style) {
 
   cm.operation(initAppliesToLineWidget);
 
-  updateMeta().then(() => {
+  const metaCompiler = createMetaCompiler(cm);
+  metaCompiler.onUpdated(meta => {
+    style.usercssData = meta;
+    style.name = meta.name;
+    style.url = meta.homepageURL;
+    updateMeta();
+  });
 
-    initLint();
+  linter.enableForEditor(cm);
+
+  updateMeta().then(() => {
 
     let prevMode = NaN;
     cm.on('optionChange', (cm, option) => {
@@ -65,7 +72,7 @@ function createSourceEditor(style) {
       const mode = getModeName();
       if (mode === prevMode) return;
       prevMode = mode;
-      updateLinter();
+      linter.run();
       updateLinterSwitch();
     });
 
@@ -88,7 +95,7 @@ function createSourceEditor(style) {
 
   function updateLinterSwitch() {
     const el = $('#editor.linter');
-    el.value = linterConfig.getName();
+    el.value = getCurrentLinter();
     const cssLintOption = $('[value="csslint"]', el);
     const mode = getModeName();
     if (mode !== 'css') {
@@ -100,6 +107,14 @@ function createSourceEditor(style) {
     }
   }
 
+  function getCurrentLinter() {
+    const name = prefs.get('editor.linter');
+    if (cm.getOption('mode') !== 'css' && name === 'csslint') {
+      return 'stylelint';
+    }
+    return name;
+  }
+
   function setupNewStyle(style) {
     style.sections[0].code = ' '.repeat(prefs.get('editor.tabSize')) +
       `/* ${t('usercssReplaceTemplateSectionBody')} */`;
diff --git a/edit/stylelint-loader.js b/edit/stylelint-loader.js
deleted file mode 100644
index d7ac7c9a..00000000
--- a/edit/stylelint-loader.js
+++ /dev/null
@@ -1,58 +0,0 @@
-/* global require importScripts */
-'use strict';
-
-importScripts('/vendor/stylelint-bundle/stylelint-bundle.min.js');
-
-const stylelint = require('stylelint');
-
-self.onmessage = ({data: {action = 'run', code, config}}) => {
-  switch (action) {
-    case 'getAllRuleIds':
-      // the functions are non-tranferable
-      self.postMessage(Object.keys(stylelint.rules));
-      return;
-    case 'getAllRuleOptions':
-      self.postMessage(getAllRuleOptions());
-      return;
-    case 'run':
-      stylelint.lint({code, config}).then(results =>
-        self.postMessage(results));
-      return;
-  }
-};
-
-function getAllRuleOptions() {
-  const options = {};
-  const rxPossible = /\bpossible:("(?:[^"]*?)"|\[(?:[^\]]*?)\]|\{(?:[^}]*?)\})/g;
-  const rxString = /"([-\w\s]{3,}?)"/g;
-  for (const id of Object.keys(stylelint.rules)) {
-    const ruleCode = String(stylelint.rules[id]);
-    const sets = [];
-    let m, mStr;
-    while ((m = rxPossible.exec(ruleCode))) {
-      const possible = m[1];
-      const set = [];
-      while ((mStr = rxString.exec(possible))) {
-        const s = mStr[1];
-        if (s.includes(' ')) {
-          set.push(...s.split(/\s+/));
-        } else {
-          set.push(s);
-        }
-      }
-      if (possible.includes('ignoreAtRules')) {
-        set.push('ignoreAtRules');
-      }
-      if (possible.includes('ignoreShorthands')) {
-        set.push('ignoreShorthands');
-      }
-      if (set.length) {
-        sets.push(set);
-      }
-    }
-    if (sets.length) {
-      options[id] = sets;
-    }
-  }
-  return options;
-}
diff --git a/edit/util.js b/edit/util.js
index f44d5d95..a16c742f 100644
--- a/edit/util.js
+++ b/edit/util.js
@@ -121,3 +121,16 @@ function sectionsToMozFormat(style) {
 function clipString(str, limit = 100) {
   return str.length <= limit ? str : str.substr(0, limit) + '...';
 }
+
+// this is a decorator. Cache the first call
+function memoize(fn) {
+  let cached = false;
+  let result;
+  return (...args) => {
+    if (!cached) {
+      result = fn(...args);
+      cached = true;
+    }
+    return result;
+  };
+}
diff --git a/package.json b/package.json
index 5aea0839..055f16e0 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
     "usercss-meta": "^0.8.1"
   },
   "scripts": {
-    "lint": "eslint **/*.js || true",
+    "lint": "eslint **/*.js --cache || exit 0",
     "update": "npm run update-node && npm run update-main",
     "update-quick": "updates -u && npm update && npm run update-main",
     "update-main": "npm run update-versions && npm run update-codemirror",
diff --git a/vendor-overwrites/csslint/csslint.js b/vendor-overwrites/csslint/csslint.js
index 7696ea96..95f74c98 100644
--- a/vendor-overwrites/csslint/csslint.js
+++ b/vendor-overwrites/csslint/csslint.js
@@ -425,7 +425,7 @@ CSSLint.addRule({
       }
     };
 
-    CSSLint.util.registerBlockEvents(parser, startRule, endRule, property);
+    CSSLint.Util.registerBlockEvents(parser, startRule, endRule, property);
   },
 });