diff --git a/app/components/Sidebar/components/HeaderBlock.js b/app/components/Sidebar/components/HeaderBlock.js
index c59e4672d..3b97dc654 100644
--- a/app/components/Sidebar/components/HeaderBlock.js
+++ b/app/components/Sidebar/components/HeaderBlock.js
@@ -23,7 +23,7 @@ function HeaderBlock({
 }: Props) {
   return (
     <Header justify="flex-start" align="center" {...rest}>
-      <TeamLogo src={logoUrl} />
+      <TeamLogo alt={`${teamName} logo`} src={logoUrl} />
       <Flex align="flex-start" column>
         <TeamName showDisclosure>
           {teamName}{' '}
diff --git a/server/static/dev.html b/server/static/dev.html
index f389e7850..60544507a 100644
--- a/server/static/dev.html
+++ b/server/static/dev.html
@@ -1,33 +1,30 @@
 <!doctype html>
-<html>
+<html lang="en">
+  <head>
+    <title>Outline</title>
+    <link href="/static/styles.css" rel="stylesheet">
+  </head>
+  <style>
+    body,
+    html {
+      margin: 0;
+      padding: 0;
+    }
 
-<head>
-  <title>Outline</title>
-  <link href="/static/styles.css" rel="stylesheet">
-</head>
-<style>
-  body,
-  html {
-    margin: 0;
-    padding: 0;
-  }
-
-  body {
-    display: flex;
-    width: 100%;
-    height: 100%;
-  }
-
-  #root {
-    flex: 1;
-    min-height: 100vh;
-  }
-</style>
-</head>
-
-<body>
-  <div id="root"></div>
-  <script src="/static/bundle.js"></script>
-</body>
+    body {
+      display: flex;
+      width: 100%;
+      height: 100%;
+    }
 
+    #root {
+      flex: 1;
+      min-height: 100vh;
+    }
+  </style>
+  </head>
+  <body>
+    <div id="root"></div>
+    <script src="/static/bundle.js"></script>
+  </body>
 </html>
\ No newline at end of file
diff --git a/server/static/index.html b/server/static/index.html
index b0f533c78..bb5c24c3f 100644
--- a/server/static/index.html
+++ b/server/static/index.html
@@ -1,32 +1,29 @@
 <!doctype html>
-<html>
+<html lang="en">
+  <head>
+    <title>Outline</title>
+    <meta name="slack-app-id" content="<%= SLACK_APP_ID %>" />
+    <style>
+      body,
+      html {
+        margin: 0;
+        padding: 0;
+      }
 
-<head>
-  <title>Outline</title>
-  <meta name="slack-app-id" content="<%= SLACK_APP_ID %>" />
-  <style>
-    body,
-    html {
-      margin: 0;
-      padding: 0;
-    }
-
-    body {
-      display: flex;
-      width: 100%;
-      height: 100%;
-    }
-
-    #root {
-      flex: 1;
-      min-height: 100vh;
-    }
-  </style>
-</head>
-
-<body>
-  <div id="root"></div>
-  <script src="//d2wy8f7a9ursnm.cloudfront.net/bugsnag-3.min.js" data-apikey="<%= BUGSNAG_KEY %>"></script>
-</body>
+      body {
+        display: flex;
+        width: 100%;
+        height: 100%;
+      }
 
+      #root {
+        flex: 1;
+        min-height: 100vh;
+      }
+    </style>
+  </head>
+  <body>
+    <div id="root"></div>
+    <script src="//d2wy8f7a9ursnm.cloudfront.net/bugsnag-3.min.js" data-apikey="<%= BUGSNAG_KEY %>"></script>
+  </body>
 </html>
