fix issue 1138 (#1139)

components/Meta.js

@@ -7,7 +7,7 @@ import Typography from './style/Typography'
 
 const CODEMIRROR_VERSION = '5.58.2'
 
-const HIGHLIGHTS_ONLY = ['shades-of-purple', 'vscode', 'a11y-dark']
+export const HIGHLIGHTS_ONLY = ['shades-of-purple', 'vscode', 'a11y-dark']
 const LOCAL_STYLESHEETS = ['one-light', 'one-dark', 'verminal', 'night-owl', 'nord', 'synthwave-84']
 const CDN_STYLESHEETS = THEMES.filter(
   t => LOCAL_STYLESHEETS.indexOf(t.id) < 0 && HIGHLIGHTS_ONLY.indexOf(t.id) < 0

pages/embed/index.js

@@ -5,7 +5,7 @@ import { withRouter } from 'next/router'
 
 // Ours
 import ApiContext from '../../components/ApiContext'
-import { StylesheetLink, CodeMirrorLink, MetaTags } from '../../components/Meta'
+import { StylesheetLink, CodeMirrorLink, MetaTags, HIGHLIGHTS_ONLY } from '../../components/Meta'
 import Font from '../../components/style/Font'
 import Carbon from '../../components/Carbon'
 import GlobalHighlights from '../../components/Themes/GlobalHighlights'
@@ -22,7 +22,7 @@ const Page = props => (
     <CodeMirrorLink />
     <Font />
     {props.children}
-    {props.theme === 'a11y-dark' && (
+    {HIGHLIGHTS_ONLY.includes(props.theme) && (
       <GlobalHighlights highlights={THEMES_HASH[props.theme].highlights} />
     )}
     <style jsx global>