diff --git a/lib/load/docs/index.js b/lib/load/docs/index.js
index 9cd9ad496d..aaaace5b51 100644
--- a/lib/load/docs/index.js
+++ b/lib/load/docs/index.js
@@ -102,9 +102,7 @@ async function loadDocs({siteDir, docsDir, env, siteConfig}) {
     })
   );
 
-  /*
-   Get the titles of the previous and next ids so that we can use them
-  */
+  /* Get the titles of the previous and next ids so that we can use them */
   Object.keys(docsMetadatas).forEach(currentID => {
     const previousID = idx(docsMetadatas, [currentID, 'previous']);
     if (previousID) {
diff --git a/lib/theme/Docs/index.js b/lib/theme/Docs/index.js
index db1b7da79e..8d4217d37f 100644
--- a/lib/theme/Docs/index.js
+++ b/lib/theme/Docs/index.js
@@ -22,16 +22,19 @@ export default class Docs extends React.Component {
               {thisSidebar[categoryName].map(rawLinkID => {
                 const linkID = (language ? `${language}-` : '') + rawLinkID;
                 const linkMetadata = docsMetadatas[linkID];
+                if (!linkMetadata) {
+                  throw new Error(
+                    `Improper sidebars.json file, document with id '${linkID}' not found.`
+                  );
+                }
                 const linkClassName =
                   linkID === thisID ? 'navListItemActive' : 'navListItem';
                 return (
-                  linkMetadata && (
-                    <li className={linkClassName} key={linkID}>
-                      <Link className="navItem" to={linkMetadata.permalink}>
-                        {linkMetadata.sidebar_label || linkMetadata.title}
-                      </Link>
-                    </li>
-                  )
+                  <li className={linkClassName} key={linkID}>
+                    <Link className="navItem" to={linkMetadata.permalink}>
+                      {linkMetadata.sidebar_label || linkMetadata.title}
+                    </Link>
+                  </li>
                 );
               })}
             </ul>
diff --git a/lib/theme/Loading.js b/lib/theme/Loading.js
index 8363912ef3..44443ff411 100644
--- a/lib/theme/Loading.js
+++ b/lib/theme/Loading.js
@@ -2,14 +2,7 @@ import React from 'react';
 
 export default props => {
   if (props.error) {
-    return (
-      <div>
-        Error!{' '}
-        <button type="button" onClick={props.retry}>
-          Retry
-        </button>
-      </div>
-    );
+    return <div align="center">Error 🔥🔥🔥</div>;
   }
   if (props.pastDelay) {
     return <div align="center">Loading...</div>;