Fixes a JS error on Private snippets as there is no share or embed button

app/assets/javascripts/snippet/snippet_embed.js

 import { __ } from '~/locale';
 
 export default () => {
-  const { protocol, host, pathname } = window.location;
   const shareBtn = document.querySelector('.js-share-btn');
+
+  if (shareBtn) {
+    const { protocol, host, pathname } = window.location;
+
     const embedBtn = document.querySelector('.js-embed-btn');
+
     const snippetUrlArea = document.querySelector('.js-snippet-url-area');
     const embedAction = document.querySelector('.js-embed-action');
     const url = `${protocol}//${host + pathname}`;
@@ -22,4 +26,5 @@ export default () => {
       snippetUrlArea.value = scriptTag;
       embedAction.innerText = __('Embed');
     });
+  }
 };

spec/features/snippets/private_snippets_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe 'Private Snippets', :js do
+  let(:user) { create(:user) }
+
+  before do
+    sign_in(user)
+  end
+
+  it 'Private Snippet renders for creator' do
+    private_snippet = create(:personal_snippet, :private, author: user)
+
+    visit snippet_path(private_snippet)
+    wait_for_requests
+
+    expect(page).to have_content(private_snippet.content)
+    expect(page).not_to have_css('.js-embed-btn')
+    expect(page).not_to have_css('.js-share-btn')
+  end
+end

spec/features/snippets/public_snippets_spec.rb

@@ -10,6 +10,8 @@ describe 'Public Snippets', :js do
     wait_for_requests
 
     expect(page).to have_content(public_snippet.content)
+    expect(page).to have_css('.js-embed-btn', visible: false)
+    expect(page).to have_css('.js-share-btn', visible: false)
   end
 
   it 'Unauthenticated user should see raw public snippets' do