diff --git a/packages/kbn-ui-shared-deps/monaco.ts b/packages/kbn-ui-shared-deps/monaco.ts
index 570aca86c484c..42801c69a3e2c 100644
--- a/packages/kbn-ui-shared-deps/monaco.ts
+++ b/packages/kbn-ui-shared-deps/monaco.ts
@@ -25,6 +25,8 @@ import 'monaco-editor/esm/vs/base/worker/defaultWorkerFactory';
 import 'monaco-editor/esm/vs/editor/browser/controller/coreCommands.js';
 import 'monaco-editor/esm/vs/editor/browser/widget/codeEditorWidget.js';
 
+import 'monaco-editor/esm/vs/editor/contrib/wordOperations/wordOperations.js'; // Needed for word-wise char navigation
+
 import 'monaco-editor/esm/vs/editor/contrib/suggest/suggestController.js'; // Needed for suggestions
 import 'monaco-editor/esm/vs/editor/contrib/hover/hover.js'; // Needed for hover
 import 'monaco-editor/esm/vs/editor/contrib/parameterHints/parameterHints.js'; // Needed for signature
diff --git a/x-pack/plugins/painless_lab/public/application/register_painless.ts b/x-pack/plugins/painless_lab/public/application/register_painless.ts
deleted file mode 100644
index a3952c1941c6e..0000000000000
--- a/x-pack/plugins/painless_lab/public/application/register_painless.ts
+++ /dev/null
@@ -1,195 +0,0 @@
-/*
- * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
- * or more contributor license agreements. Licensed under the Elastic License;
- * you may not use this file except in compliance with the Elastic License.
- */
-
-import * as monaco from 'monaco-editor/esm/vs/editor/editor.api';
-export const LANGUAGE_ID = 'painless';
-
-/**
- * Extends the default type for a Monarch language so we can use
- * attribute references (like @keywords to reference the keywords list)
- * in the defined tokenizer
- */
-interface Language extends monaco.languages.IMonarchLanguage {
-  default: string;
-  brackets: any;
-  keywords: string[];
-  symbols: RegExp;
-  escapes: RegExp;
-  digits: RegExp;
-  primitives: string[];
-  octaldigits: RegExp;
-  binarydigits: RegExp;
-  constants: string[];
-  operators: string[];
-}
-
-function getPainlessLanguage() {
-  return {
-    default: '',
-    // painless does not use < >, so we define our own
-    brackets: [
-      ['{', '}', 'delimiter.curly'],
-      ['[', ']', 'delimiter.square'],
-      ['(', ')', 'delimiter.parenthesis'],
-    ],
-    keywords: [
-      'if',
-      'in',
-      'else',
-      'while',
-      'do',
-      'for',
-      'continue',
-      'break',
-      'return',
-      'new',
-      'try',
-      'catch',
-      'throw',
-      'this',
-      'instanceof',
-    ],
-    primitives: [
-      'void',
-      'boolean',
-      'byte',
-      'short',
-      'char',
-      'int',
-      'long',
-      'float',
-      'double',
-      'def',
-    ],
-    constants: ['true', 'false'],
-    operators: [
-      '=',
-      '>',
-      '<',
-      '!',
-      '~',
-      '?',
-      '?:',
-      '?.',
-      ':',
-      '==',
-      '===',
-      '<=',
-      '>=',
-      '!=',
-      '!==',
-      '&&',
-      '||',
-      '++',
-      '--',
-      '+',
-      '-',
-      '*',
-      '/',
-      '&',
-      '|',
-      '^',
-      '%',
-      '<<',
-      '>>',
-      '>>>',
-      '+=',
-      '-=',
-      '*=',
-      '/=',
-      '&=',
-      '|=',
-      '^=',
-      '%=',
-      '<<=',
-      '>>=',
-      '>>>=',
-      '->',
-      '::',
-      '=~',
-      '==~',
-    ],
-    symbols: /[=><!~?:&|+\-*\/^%]+/,
-    escapes: /\\(?:[abfnrtv\\"']|x[0-9A-Fa-f]{1,4}|u[0-9A-Fa-f]{4}|U[0-9A-Fa-f]{8})/,
-    digits: /\d+(_+\d+)*/,
-    octaldigits: /[0-7]+(_+[0-7]+)*/,
-    binarydigits: /[0-1]+(_+[0-1]+)*/,
-    hexdigits: /[[0-9a-fA-F]+(_+[0-9a-fA-F]+)*/,
-    tokenizer: {
-      root: [
-        // identifiers and keywords
-        [
-          /[a-zA-Z_][\w]*/,
-          {
-            cases: {
-              '@keywords': 'keyword',
-              '@primitives': 'type',
-              '@constants': 'constant',
-              '@default': 'identifier',
-            },
-          },
-        ],
-        // whitespace
-        [/[ \t\r\n]+/, '@whitespace'],
-        // comments
-        // [/\/\*/, 'comment', '@comment'],
-        [/\/\/.*$/, 'comment'],
-        // brackets
-        [/[{}()\[\]]/, '@brackets'],
-        // operators
-        [
-          /@symbols/,
-          {
-            cases: {
-              '@operators': 'operators',
-              '@default': '',
-            },
-          },
-        ],
-        // numbers
-        [/(@digits)[eE]([\-+]?(@digits))?[fFdD]?/, 'number.float'],
-        [/(@digits)\.(@digits)([eE][\-+]?(@digits))?[fFdD]?/, 'number.float'],
-        [/0[xX](@hexdigits)[Ll]?/, 'number.hex'],
-        [/0(@octaldigits)[Ll]?/, 'number.octal'],
-        [/0[bB](@binarydigits)[Ll]?/, 'number.binary'],
-        [/(@digits)[fFdD]/, 'number.float'],
-        [/(@digits)[lL]?/, 'number'],
-        // delimiter: after numbers due to conflict with decimals and dot
-        [/[;,.]/, 'delimiter'],
-        // strings double quoted
-        [/"([^"\\]|\\.)*$/, 'string.invalid'], // string without termination
-        [/"/, 'string', '@string_dq'],
-        // strings single quoted
-        [/'([^'\\]|\\.)*$/, 'string.invalid'], // string without termination
-        [/'/, 'string', '@string_sq'],
-      ],
-      comment: [
-        [/[^\/*]+/, 'comment'],
-        [/\*\//, 'comment', '@pop'],
-        [/[\/*]/, 'comment'],
-      ],
-      string_dq: [
-        [/[^\\"]+/, 'string'],
-        [/@escapes/, 'string.escape'],
-        [/\\./, 'string.escape.invalid'],
-        [/"/, 'string', '@pop'],
-      ],
-      string_sq: [
-        [/[^\\']+/, 'string'],
-        [/@escapes/, 'string.escape'],
-        [/\\./, 'string.escape.invalid'],
-        [/'/, 'string', '@pop'],
-      ],
-    },
-  } as Language;
-}
-
-export function registerPainless() {
-  // TODO: Referring to `window.monaco` is a temporary fix for the imported `monaco`  module not
-  // being the same one in use by the editor.
-  (window as any).monaco.languages.register({ id: LANGUAGE_ID });
-  (window as any).monaco.languages.setMonarchTokensProvider(LANGUAGE_ID, getPainlessLanguage());
-}
diff --git a/x-pack/plugins/painless_lab/public/index.ts b/x-pack/plugins/painless_lab/public/index.ts
index f81218a4fcd96..da357e52af676 100644
--- a/x-pack/plugins/painless_lab/public/index.ts
+++ b/x-pack/plugins/painless_lab/public/index.ts
@@ -5,9 +5,8 @@
  */
 
 import './styles/_index.scss';
-import { PluginInitializerContext } from 'src/core/public';
 import { PainlessLabUIPlugin } from './plugin';
 
-export function plugin(ctx: PluginInitializerContext) {
-  return new PainlessLabUIPlugin(ctx);
+export function plugin() {
+  return new PainlessLabUIPlugin();
 }
diff --git a/x-pack/plugins/painless_lab/public/lib/index.ts b/x-pack/plugins/painless_lab/public/lib/index.ts
new file mode 100644
index 0000000000000..2421307b7c107
--- /dev/null
+++ b/x-pack/plugins/painless_lab/public/lib/index.ts
@@ -0,0 +1,7 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+export { monacoPainlessLang } from './monaco_painless_lang';
diff --git a/x-pack/plugins/painless_lab/public/lib/monaco_painless_lang.ts b/x-pack/plugins/painless_lab/public/lib/monaco_painless_lang.ts
new file mode 100644
index 0000000000000..602697064a768
--- /dev/null
+++ b/x-pack/plugins/painless_lab/public/lib/monaco_painless_lang.ts
@@ -0,0 +1,174 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+import * as monaco from 'monaco-editor';
+
+/**
+ * Extends the default type for a Monarch language so we can use
+ * attribute references (like @keywords to reference the keywords list)
+ * in the defined tokenizer
+ */
+interface Language extends monaco.languages.IMonarchLanguage {
+  default: string;
+  brackets: any;
+  keywords: string[];
+  symbols: RegExp;
+  escapes: RegExp;
+  digits: RegExp;
+  primitives: string[];
+  octaldigits: RegExp;
+  binarydigits: RegExp;
+  constants: string[];
+  operators: string[];
+}
+
+export const monacoPainlessLang = {
+  default: '',
+  // painless does not use < >, so we define our own
+  brackets: [
+    ['{', '}', 'delimiter.curly'],
+    ['[', ']', 'delimiter.square'],
+    ['(', ')', 'delimiter.parenthesis'],
+  ],
+  keywords: [
+    'if',
+    'in',
+    'else',
+    'while',
+    'do',
+    'for',
+    'continue',
+    'break',
+    'return',
+    'new',
+    'try',
+    'catch',
+    'throw',
+    'this',
+    'instanceof',
+  ],
+  primitives: ['void', 'boolean', 'byte', 'short', 'char', 'int', 'long', 'float', 'double', 'def'],
+  constants: ['true', 'false'],
+  operators: [
+    '=',
+    '>',
+    '<',
+    '!',
+    '~',
+    '?',
+    '?:',
+    '?.',
+    ':',
+    '==',
+    '===',
+    '<=',
+    '>=',
+    '!=',
+    '!==',
+    '&&',
+    '||',
+    '++',
+    '--',
+    '+',
+    '-',
+    '*',
+    '/',
+    '&',
+    '|',
+    '^',
+    '%',
+    '<<',
+    '>>',
+    '>>>',
+    '+=',
+    '-=',
+    '*=',
+    '/=',
+    '&=',
+    '|=',
+    '^=',
+    '%=',
+    '<<=',
+    '>>=',
+    '>>>=',
+    '->',
+    '::',
+    '=~',
+    '==~',
+  ],
+  symbols: /[=><!~?:&|+\-*\/^%]+/,
+  escapes: /\\(?:[abfnrtv\\"']|x[0-9A-Fa-f]{1,4}|u[0-9A-Fa-f]{4}|U[0-9A-Fa-f]{8})/,
+  digits: /\d+(_+\d+)*/,
+  octaldigits: /[0-7]+(_+[0-7]+)*/,
+  binarydigits: /[0-1]+(_+[0-1]+)*/,
+  hexdigits: /[[0-9a-fA-F]+(_+[0-9a-fA-F]+)*/,
+  tokenizer: {
+    root: [
+      // identifiers and keywords
+      [
+        /[a-zA-Z_][\w]*/,
+        {
+          cases: {
+            '@keywords': 'keyword',
+            '@primitives': 'type',
+            '@constants': 'constant',
+            '@default': 'identifier',
+          },
+        },
+      ],
+      // whitespace
+      [/[ \t\r\n]+/, '@whitespace'],
+      // comments
+      // [/\/\*/, 'comment', '@comment'],
+      [/\/\/.*$/, 'comment'],
+      // brackets
+      [/[{}()\[\]]/, '@brackets'],
+      // operators
+      [
+        /@symbols/,
+        {
+          cases: {
+            '@operators': 'operators',
+            '@default': '',
+          },
+        },
+      ],
+      // numbers
+      [/(@digits)[eE]([\-+]?(@digits))?[fFdD]?/, 'number.float'],
+      [/(@digits)\.(@digits)([eE][\-+]?(@digits))?[fFdD]?/, 'number.float'],
+      [/0[xX](@hexdigits)[Ll]?/, 'number.hex'],
+      [/0(@octaldigits)[Ll]?/, 'number.octal'],
+      [/0[bB](@binarydigits)[Ll]?/, 'number.binary'],
+      [/(@digits)[fFdD]/, 'number.float'],
+      [/(@digits)[lL]?/, 'number'],
+      // delimiter: after numbers due to conflict with decimals and dot
+      [/[;,.]/, 'delimiter'],
+      // strings double quoted
+      [/"([^"\\]|\\.)*$/, 'string.invalid'], // string without termination
+      [/"/, 'string', '@string_dq'],
+      // strings single quoted
+      [/'([^'\\]|\\.)*$/, 'string.invalid'], // string without termination
+      [/'/, 'string', '@string_sq'],
+    ],
+    comment: [
+      [/[^\/*]+/, 'comment'],
+      [/\*\//, 'comment', '@pop'],
+      [/[\/*]/, 'comment'],
+    ],
+    string_dq: [
+      [/[^\\"]+/, 'string'],
+      [/@escapes/, 'string.escape'],
+      [/\\./, 'string.escape.invalid'],
+      [/"/, 'string', '@pop'],
+    ],
+    string_sq: [
+      [/[^\\']+/, 'string'],
+      [/@escapes/, 'string.escape'],
+      [/\\./, 'string.escape.invalid'],
+      [/'/, 'string', '@pop'],
+    ],
+  },
+} as Language;
diff --git a/x-pack/plugins/painless_lab/public/plugin.tsx b/x-pack/plugins/painless_lab/public/plugin.tsx
index 57166c5d312a7..f24e0f9c472d7 100644
--- a/x-pack/plugins/painless_lab/public/plugin.tsx
+++ b/x-pack/plugins/painless_lab/public/plugin.tsx
@@ -6,7 +6,7 @@
 
 import React from 'react';
 import { i18n } from '@kbn/i18n';
-import { Plugin, CoreStart, CoreSetup, PluginInitializerContext } from 'kibana/public';
+import { Plugin, CoreStart, CoreSetup } from 'kibana/public';
 import { first } from 'rxjs/operators';
 import { EuiBetaBadge, EuiFlexGroup, EuiFlexItem } from '@elastic/eui';
 
@@ -15,10 +15,10 @@ import { LICENSE_CHECK_STATE } from '../../licensing/public';
 
 import { PLUGIN } from '../common/constants';
 import { PluginDependencies } from './types';
-import { registerPainless } from './application/register_painless';
+import { LanguageService } from './services';
 
 export class PainlessLabUIPlugin implements Plugin<void, void, PluginDependencies> {
-  constructor(ctx: PluginInitializerContext) {}
+  languageService = new LanguageService();
 
   async setup(
     { http, getStartServices, uiSettings }: CoreSetup,
@@ -71,7 +71,7 @@ export class PainlessLabUIPlugin implements Plugin<void, void, PluginDependencie
           notifications,
         } = core;
 
-        registerPainless();
+        this.languageService.setup();
 
         const license = await licensing.license$.pipe(first()).toPromise();
         const { state, message: invalidLicenseMessage } = license.check(
@@ -94,5 +94,7 @@ export class PainlessLabUIPlugin implements Plugin<void, void, PluginDependencie
 
   async start(core: CoreStart, plugins: any) {}
 
-  async stop() {}
+  async stop() {
+    this.languageService.stop();
+  }
 }
diff --git a/x-pack/plugins/painless_lab/public/services/index.ts b/x-pack/plugins/painless_lab/public/services/index.ts
new file mode 100644
index 0000000000000..20bec9de24550
--- /dev/null
+++ b/x-pack/plugins/painless_lab/public/services/index.ts
@@ -0,0 +1,7 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+export { LanguageService } from './language_service';
diff --git a/x-pack/plugins/painless_lab/public/services/language_service.ts b/x-pack/plugins/painless_lab/public/services/language_service.ts
new file mode 100644
index 0000000000000..efff9cd0e78d5
--- /dev/null
+++ b/x-pack/plugins/painless_lab/public/services/language_service.ts
@@ -0,0 +1,45 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+// It is important that we use this specific monaco instance so that
+// editor settings are registered against the instance our React component
+// uses.
+import { monaco } from '@kbn/ui-shared-deps/monaco';
+
+// @ts-ignore
+import workerSrc from 'raw-loader!monaco-editor/min/vs/base/worker/workerMain.js';
+
+import { monacoPainlessLang } from '../lib';
+
+const LANGUAGE_ID = 'painless';
+
+// Safely check whether these globals are present
+const CAN_CREATE_WORKER = typeof Blob === 'function' && typeof Worker === 'function';
+
+export class LanguageService {
+  private originalMonacoEnvironment: any;
+
+  public setup() {
+    monaco.languages.register({ id: LANGUAGE_ID });
+    monaco.languages.setMonarchTokensProvider(LANGUAGE_ID, monacoPainlessLang);
+
+    if (CAN_CREATE_WORKER) {
+      this.originalMonacoEnvironment = (window as any).MonacoEnvironment;
+      (window as any).MonacoEnvironment = {
+        getWorker: () => {
+          const blob = new Blob([workerSrc], { type: 'application/javascript' });
+          return new Worker(window.URL.createObjectURL(blob));
+        },
+      };
+    }
+  }
+
+  public stop() {
+    if (CAN_CREATE_WORKER) {
+      (window as any).MonacoEnvironment = this.originalMonacoEnvironment;
+    }
+  }
+}