Remove multiple new lines (#382)

Allow no more than one empty line.

files/en-us/games/techniques/2d_collision_detection/index.html

@@ -145,7 +145,6 @@ <h6 id="Playable_code">Playable code</h6>
     }
 });
 
-
 </pre>
 </div>
 

files/en-us/games/techniques/3d_collision_detection/bounding_volume_collision_detection_with_three.js/index.html

@@ -33,8 +33,6 @@ <h3 id="Instantiating_boxes">Instantiating boxes</h3>
   knot.geometry.boundingBox.max);
 </pre>
 
-
-
 <div class="note">
 <p><strong>Note</strong>: The <code>boundingBox</code> property takes the <code>Geometry</code> itself as reference, and not the <code>Mesh</code>. So any transformations such as scale, position, etc. applied to the <code>Mesh</code> will be ignored while computing the calculating box.</p>
 </div>

files/en-us/games/techniques/controls_gamepad_api/index.html

@@ -17,7 +17,6 @@ <h2 id="Controls_for_web_games">Controls for web games</h2>
 
 <p>Historically playing games on a console connected to your TV was always a totally different experience to gaming on the PC, mostly because of the unique controls. Eventually, extra drivers and plugins allowed us to use console gamepads with desktop games — either native games or those running in the browser. Now in the era of HTML5, we finally have the <a href="/en-US/docs/Web/API/Gamepad_API">Gamepad API</a>, which gives us the ability to play browser-based games using gamepad controllers without any plugins. The Gamepad API achieves this by providing an interface exposing button presses and axis changes that can be used inside JavaScript code to handle the input. These are good times for browser gaming.</p>
 
-
 <h2 id="API_status_and_browser_support">API status and browser support</h2>
 
 <p>The <a href="http://www.w3.org/TR/gamepad/">Gamepad API</a> is still at the Working Draft stage in the W3C process, which means its implementation might still change, but saying that the <a href="http://caniuse.com/gamepad">browser support</a> is already quite good. Firefox 29+ and Chrome 35+ support it out of the box. Opera supports the API in version 22+ (not surprising given that they now use Chrome's Blink engine.) And Microsoft implemented support for the API in Edge recently, which means four main browsers now supporting the Gamepad API.</p>

files/en-us/games/techniques/efficient_animation_for_web_games/index.html

@@ -95,8 +95,6 @@ <h2 id="A_take-away">A take-away</h2>
 
 <p>{{EmbedYouTube("hap4iQTMh70")}}</p>
 
-
-
 <div class="note">
 <p><strong>Note</strong>: This article was originally written and published by Chris Lord, on his blog — see <a href="http://chrislord.net/index.php/2013/11/29/efficient-animation-for-games-on-the-mobile-web/">Efficient animation for games on the (mobile) web</a>.</p>
 </div>

files/en-us/games/techniques/tilemaps/index.html

@@ -84,7 +84,6 @@ <h4 id="Positioning_and_camera">Positioning and camera</h4>
   return {x: x - camera.x, y: y - camera.y};
 }
 
-
 function screenToWorld(x,y) {
   return {x: x + camera.x, y: y + camera.y};
 }</pre>

files/en-us/games/tutorials/2d_breakout_game_pure_javascript/finishing_up/index.html

@@ -41,10 +41,6 @@ <h2 id="Giving_the_player_some_lives">Giving the player some lives</h2>
 clearInterval(interval); // Needed for Chrome to end game
 </pre>
 
-
-
-
-
 <p>With this, we can add slightly more complex logic to it as given below:</p>
 
 <pre class="brush: js notranslate">lives--;

files/en-us/games/tutorials/2d_breakout_game_pure_javascript/game_over/index.html

@@ -36,20 +36,14 @@ <h2 id="Implementing_game_over">Implementing game over</h2>
 
 <p>First, replace where you initially called <code>setInterval()</code></p>
 
-
-
 <pre class="notranslate">setInterval(draw, 10);
 </pre>
 
 <p>with:</p>
 
-
-
 <pre class="notranslate">var interval = setInterval(draw, 10);
 </pre>
 
-
-
 <p>Then replace the second if statement with the following:</p>
 
 <pre class="brush: js notranslate">if(y + dy &lt; ballRadius) {

files/en-us/glossary/boolean/index.html

@@ -24,7 +24,6 @@
   console.log("boolean conditional resolved to false");
 }
 
-
 /* JavaScript for loop */
 for (<em>control variable</em>; <em>boolean conditional</em>; <em>counter</em>) {
   // code to execute repeatedly if the conditional is true

files/en-us/glossary/document_directive/index.html

@@ -15,8 +15,6 @@
 
 <p>See <a href="/en-US/docs/Web/HTTP/Headers/Content-Security-Policy#Document_directives">Document directives</a> for a complete list.</p>
 
-
-
 <section class="Quick_links" id="Quick_Links">
 <ol>
  <li><a href="/en-US/docs/Glossary">Glossary</a>

files/en-us/glossary/fetch_directive/index.html

@@ -12,8 +12,6 @@
 
 <p>See <a href="/en-US/docs/Web/HTTP/Headers/Content-Security-Policy#Fetch_directives">Fetch directives</a> for a complete list.</p>
 
-
-
 <section class="Quick_links" id="Quick_Links">
 <ol>
  <li><a href="/en-US/docs/Glossary">Glossary</a>

files/en-us/glossary/fetch_metadata_request_header/index.html

@@ -18,7 +18,6 @@
  <li>{{HTTPHeader("Sec-Fetch-Dest")}}</li>
 </ul>
 
-
 <section class="Quick_links" id="Quick_Links">
 <ol>
  <li>Fetch Me

files/en-us/glossary/gzip_compression/index.html

@@ -8,8 +8,6 @@
 ---
 <p>Gzip is a file format used for file compression and decompression. It is based on the Deflate algorithm that allows files to be made smaller in size which allows for faster network transfers. Gzip is commonly supported by web servers and modern browsers, meaning that servers can automatically compress files with Gzip before sending them, and browsers can uncompress files upon receiving them.</p>
 
-
-
 <h2 id="Learn_more">Learn more</h2>
 
 <ul>

files/en-us/glossary/hoisting/index.html

@@ -77,7 +77,6 @@ <h3 id="Only_declarations_are_hoisted">Only declarations are hoisted</h3>
 // This prints value of y as undefined as JavaScript only hoists declarations
 var y = 2; // Declare and Initialize y
 
-
 // Example 2
 // No hoisting, but since initialization also causes declaration (if not already declared), variables are available.
 

files/en-us/glossary/mutable/index.html

@@ -35,8 +35,6 @@
  <li>Previously created memory space is now available for garbage collection.</li>
 </ol>
 
-
-
 <h2 id="Learn_more">Learn more</h2>
 
 <h3 id="General_knowledge">General knowledge</h3>

files/en-us/glossary/reporting_directive/index.html

@@ -13,8 +13,6 @@
 
 <p>See <a href="/en-US/docs/Web/HTTP/Headers/Content-Security-Policy#Reporting_directives">Reporting directives</a> for a complete list.</p>
 
-
-
 <section class="Quick_links" id="Quick_Links">
 <ol>
  <li><a href="/en-US/docs/Glossary">Glossary</a>

files/en-us/glossary/resource_timing/index.html

@@ -10,8 +10,6 @@
 
 <h2 id="See_also">See also</h2>
 
-
-
 <ul>
  <li><a href="/en-US/docs/Web/API/Resource_Timing_API/Using_the_Resource_Timing_API">Using the resource timing API</a></li>
  <li><a href="https://www.w3.org/TR/server-timing/">Server Timing</a></li>

files/en-us/glossary/speculative_parsing/index.html

@@ -15,8 +15,6 @@
 
 <p>To make speculative loads of linked scripts, style sheets and images successful, avoid {{domxref('document.write')}}. If you use a <code>&lt;base&gt;</code> element to override the base URI of your page, put the element in the non-scripted part of the document. Don't add it via <code>document.write()</code> or {{domxref('document.createElement')}}.</p>
 
-
-
 <h2 id="Avoiding_losing_tree_builder_output">Avoiding losing tree builder output</h2>
 
 <p>Speculative tree building fails when <code>document.write()</code> changes the tree builder state such that the speculative state after the <code>&lt;/script&gt;</code> tag no longer holds when all the content inserted by <code>document.write()</code> has been parsed. However, only unusual uses of <code>document.write()</code> cause trouble. Here are the things to avoid:</p>

files/en-us/glossary/webdav/index.html

@@ -19,7 +19,6 @@
  <li>lock a document from being edited by more than one person at a time</li>
 </ul>
 
-
 <h2 id="See_also">Learn more</h2>
 
 <h3 id="General_Knowledge">General Knowledge</h3>

files/en-us/learn/accessibility/html/index.html

@@ -457,7 +457,6 @@ <h2 id="Text_alternatives">Text alternatives</h2>
      alt="A red Tyrannosaurus Rex: A two legged dinosaur standing upright like a human, with small arms, and a large head with lots of sharp teeth."
      title="The Mozilla red dinosaur"&gt;
 
-
 &lt;img src="dinosaur.png" aria-labelledby="dino-label"&gt;
 
 &lt;p id="dino-label"&gt;The Mozilla red Tyrannosaurus Rex: A two legged dinosaur standing upright like a human, with small arms, and a large head with lots of sharp teeth.&lt;/p&gt;

files/en-us/learn/css/building_blocks/styling_tables/index.html

@@ -274,8 +274,6 @@ <h3 id="Styling_the_caption">Styling the caption</h3>
 
 <p><img alt="" src="https://mdn.mozillademos.org/files/13076/table-with-caption.png" style="display: block; height: 357px; margin: 0px auto; width: 723px;"></p>
 
-
-
 <h2 id="Table_styling_quick_tips">Table styling quick tips</h2>
 
 <p>Before moving on, we thought we'd provide you with a quick list of the most useful points illustrated above:</p>

files/en-us/learn/css/css_layout/introduction/index.html

@@ -679,7 +679,6 @@ <h6 id="Multicol_example">Multicol example</h6>
 
         &lt;p&gt; Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nulla luctus aliquam dolor, eu lacinia lorem placerat vulputate. Duis felis orci, pulvinar id metus ut, rutrum luctus orci. Cras porttitor imperdiet nunc, at ultricies tellus laoreet sit amet. Sed auctor cursus massa at porta. Integer ligula ipsum, tristique sit amet orci vel, viverra egestas ligula. Curabitur vehicula tellus neque, ac ornare ex malesuada et. In vitae convallis lacus. Aliquam erat volutpat. Suspendisse ac imperdiet turpis. Aenean finibus sollicitudin eros pharetra congue. Duis ornare egestas augue ut luctus. Proin blandit quam nec lacus varius commodo et a urna. Ut id ornare felis, eget fermentum sapien.&lt;/p&gt;
 
-
         &lt;p&gt;Nam vulputate diam nec tempor bibendum. Donec luctus augue eget malesuada ultrices. Phasellus turpis est, posuere sit amet dapibus ut, facilisis sed est. Nam id risus quis ante semper consectetur eget aliquam lorem. Vivamus tristique elit dolor, sed pretium metus suscipit vel. Mauris ultricies lectus sed lobortis finibus. Vivamus eu urna eget velit cursus viverra quis vestibulum sem. Aliquam tincidunt eget purus in interdum. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus.&lt;/p&gt;
 
     &lt;/div&gt;

files/en-us/learn/css/css_layout/legacy_layout_methods/index.html

@@ -434,7 +434,6 @@ <h2 id="Flexbox_grids">Flexbox grids?</h2>
   padding-right: 2.08333333%;
 }
 
-
 .row {
   display: flex;
 }

files/en-us/learn/css/css_layout/practical_positioning_examples/index.html

@@ -400,8 +400,6 @@ <h2 id="Summary">Summary</h2>
 
 <p>So that rounds off our look at positioning — by now, you should have an idea of how the basic mechanics work, as well as understanding how to start applying these to build some interesting UI features. Don't worry if you didn't get this all immediately — positioning is a fairly advanced topic, and you can always work through the articles again to aid your understanding. The next subject we'll turn to is Flexbox.</p>
 
-
-
 <h2 id="In_this_module">In this module</h2>
 
 <ul>

files/en-us/learn/css/first_steps/index.html

@@ -13,7 +13,6 @@
 
 <p class="summary">CSS (Cascading Style Sheets) is used to style and lay out web pages — for example, to alter the font, color, size, and spacing of your content, split it into multiple columns, or add animations and other decorative features. This module provides a gentle beginning to your path towards CSS mastery with the basics of how it works, what the syntax looks like, and how you can start using it to add styling to HTML.</p>
 
-
 <div class="in-page-callout webdev">
 <h3 id="Looking_to_become_a_front-end_web_developer">Looking to become a front-end web developer?</h3>
 

files/en-us/learn/css/styling_text/styling_links/index.html

@@ -108,7 +108,6 @@ <h3 id="Styling_some_links">Styling some links</h3>
 
 }
 
-
 a:link {
 
 }

files/en-us/learn/css/styling_text/styling_lists/index.html

@@ -113,7 +113,6 @@ <h2 id="Handling_list_spacing">Handling list spacing</h2>
 
 /* Description list styles */
 
-
 dd, dt {
   line-height: 1.5;
 }

files/en-us/learn/forms/index.html

@@ -15,7 +15,6 @@
 
 <p class="summary">This module provides a series of articles that will help you master the essentials of web forms. Web forms are a very powerful tool for interacting with users — most commonly they are used for collecting data from users, or allowing them to control a user interface. However, for historical and technical reasons it's not always obvious how to use them to their full potential. In the articles listed below, we'll cover all the essential aspects of Web forms including marking up their HTML structure, styling form controls, validating form data, and submitting data to the server.</p>
 
-
 <div class="in-page-callout webdev">
 <h3 id="Looking_to_become_a_front-end_web_developer">Looking to become a front-end web developer?</h3>
 
@@ -76,8 +75,6 @@ <h2 id="Validating_and_submitting_form_data">Validating and submitting form data
  <dd>This article looks at what happens when a user submits a form — where does the data go, and how do we handle it when it gets there? We also look at some of the security concerns associated with sending form data.</dd>
 </dl>
 
-
-
 <h2 id="Advanced_articles">Advanced articles</h2>
 
 <p>The following articles aren't essential to the learning pathway, but they'll prove interesting and useful when you've mastered the above techniques and want to know more.</p>

files/en-us/learn/html/howto/add_a_hit_map_on_top_of_an_image/index.html

@@ -100,7 +100,6 @@ <h3 id="Step_2_Activate_your_hotspots">Step 2: Activate your hotspots</h3>
   &lt;area shape="circle" coords="200,250,25"
     href="page-2.html" alt="circle example" /&gt;
 
-
   &lt;area shape="rect" coords="10, 5, 20, 15"
     href="page-3.html" alt="rectangle example" /&gt;
 

files/en-us/learn/html/introduction_to_html/advanced_text_formatting/index.html

@@ -614,7 +614,6 @@ <h2 id="Representing_computer_code">Representing computer code</h2>
 
 &lt;p&gt;In the above JavaScript example, &lt;var&gt;para&lt;/var&gt; represents a paragraph element.&lt;/p&gt;
 
-
 &lt;p&gt;Select all the text with &lt;kbd&gt;Ctrl&lt;/kbd&gt;/&lt;kbd&gt;Cmd&lt;/kbd&gt; + &lt;kbd&gt;A&lt;/kbd&gt;.&lt;/p&gt;
 
 &lt;pre&gt;$ &lt;kbd&gt;ping mozilla.org&lt;/kbd&gt;

files/en-us/learn/javascript/building_blocks/conditionals/index.html

@@ -316,7 +316,6 @@ <h3 id="A_switch_example">A switch example</h3>
 
 select.addEventListener('change', setWeather);
 
-
 function setWeather() {
   const choice = select.value;
 

files/en-us/learn/javascript/building_blocks/looping_code/index.html

@@ -110,7 +110,6 @@ <h6 id="Hidden_code">Hidden code</h6>
 
   &lt;canvas&gt;&lt;/canvas&gt;
 
-
     &lt;script&gt;
     const btn = document.querySelector('button');
     const canvas = document.querySelector('canvas');
@@ -223,7 +222,6 @@ <h6 id="Hidden_code_2">Hidden code 2</h6>
 
   &lt;p&gt;&lt;/p&gt;
 
-
     &lt;script&gt;
     const cats = ['Bill', 'Jeff', 'Pete', 'Biggles', 'Jasmin'];
     let info = 'My cats are called ';
@@ -350,7 +348,6 @@ <h6 id="Hidden_code_3">Hidden code 3</h6>
 
   &lt;p&gt;&lt;/p&gt;
 
-
     &lt;script&gt;
     const contacts = ['Chris:2232322', 'Sarah:3453456', 'Bill:7654322', 'Mary:9998769', 'Dianne:9384975'];
     const para = document.querySelector('p');
@@ -437,7 +434,6 @@ <h6 id="Hidden_code_4">Hidden code 4</h6>
 
   &lt;p&gt;Output: &lt;/p&gt;
 
-
     &lt;script&gt;
     const para = document.querySelector('p');
     const input = document.querySelector('input');

files/en-us/learn/javascript/client-side_web_apis/index.html

@@ -20,7 +20,6 @@
 
 <p class="summary">When writing client-side JavaScript for web sites or applications, you will quickly encounter <strong>Application Programming Interfaces</strong> (<strong>APIs</strong>). APIs are programming features for manipulating different aspects of the browser and operating system the site is running on, or manipulating data from other web sites or services. In this module, we will explore what APIs are, and how to use some of the most common APIs you'll come across often in your development work. </p>
 
-
 <div class="in-page-callout webdev">
 <h3 id="Looking_to_become_a_front-end_web_developer">Looking to become a front-end web developer?</h3>
 

files/en-us/learn/javascript/first_steps/arrays/index.html

@@ -297,7 +297,6 @@ <h6 id="Playable_code">Playable code</h6>
     insertAtCaret('\t');
   }
 
-
   if (e.keyCode === 27) {
     textarea.blur();
   }
@@ -389,7 +388,6 @@ <h6 id="Playable_code_2">Playable code 2</h6>
 
 &lt;p class="a11y-label"&gt;Press Esc to move focus away from the code area (Tab inserts a tab character).&lt;/p&gt;
 
-
 &lt;textarea id="code" class="playable-code" style="height: 370px; width: 95%"&gt;
 const list = document.querySelector('.output ul');
 const searchInput = document.querySelector('.output input');

files/en-us/learn/javascript/first_steps/index.html

@@ -22,7 +22,6 @@
 
 <p class="summary">In our first JavaScript module, we first answer some fundamental questions such as "what is JavaScript?", "what does it look like?", and "what can it do?", before moving on to taking you through your first practical experience of writing JavaScript. After that, we discuss some key building blocks in detail, such as variables, strings, numbers and arrays.</p>
 
-
 <div class="in-page-callout webdev">
 <h3 id="Looking_to_become_a_front-end_web_developer">Looking to become a front-end web developer?</h3>
 

files/en-us/learn/performance/business_case_for_performance/index.html

@@ -30,7 +30,6 @@ <h2 id="Making_performance_a_business_priority">Making performance a business pr
 
 <p>We've discussed how prioritizing performance can improve user experience and therefore revenue. We know that not prioritizing web performance can result in a loss of business revenue. This article discusses how certain business metrics directly relate to a user's web performance experience and how to apply service design to boost the user's experiences of web performance. It highlights the importance of understanding how cumulative experiences impact conversion and retention rates.</p>
 
-
 <h3 id="Performance_budgets">Performance budgets</h3>
 
 <p>Setting a web performance budget can help you make sure the team stays on track in keeping the site and help prevent regressions. A performance budget is a set of limits that are set to specify limits, such as the maximum number of HTTP requests allowed, the maximum total size of all the assets combined, the minimum allowable FPS on a specific device, etc, that must be maintained.  The budget can be applied to a single file, a file type, all files loaded on a page, a specific metric, or a threshold over a period of time. The budget reflects reachable goals; whether they are time, quantity, or rule-based.</p>

files/en-us/learn/performance/javascript_performance/index.html

@@ -47,7 +47,6 @@ <h2 id="Download_impact">Download impact</h2>
  <dd></dd>
 </dl>
 
-
 <h2 id="Render_impact">Render impact</h2>
 
 <p>Web applications include a lot of JavaScript. Many applications are built with a JavaScrpit framework, or multiple, with several additional dependencies. Often times third party scripts and APIs are added, including A/B testing, tracking pixels, and features like maps and support features.</p>

files/en-us/learn/performance/video/index.html

@@ -84,8 +84,6 @@ <h3 id="Remove_audio_from_muted_hero_videos">Remove audio from muted hero videos
 
 <pre><a href="https://www.ffmpeg.org/">ffmpeg</a> -i original.mp4 -an -c:v copy audioFreeVersion.mp4</pre>
 
-
-
 <h3 id="Video_preload">Video preload</h3>
 
 <p>The preload attribute has three available options: <code>auto</code>|<code>metadata</code>|<code>none</code>. The default setting is <code>metadata</code>. These settings control how much of a video file downloads with page load. You can save data by deferring download for less popular videos.</p>

files/en-us/learn/server-side/django/introduction/index.html

@@ -208,7 +208,6 @@ <h3 id="Querying_data_views.py">Querying data (views.py)</h3>
     return render(request, '/best/index.html', context)
 </pre>
 
-
 <p>This function uses the <code>render()</code> function to create the <code>HttpResponse</code> that is sent back to the browser. This function is a <em>shortcut</em>; it creates an HTML file by combining a specified HTML template and some data to insert in the template (provided in the variable named "<code>context</code>"). In the next section we show how the template has the data inserted in it to create the HTML.</p>
 
 <h3 id="Rendering_data_HTML_templates">Rendering data (HTML templates)</h3>

files/en-us/learn/server-side/express_nodejs/forms/create_genre_form/index.html

@@ -58,7 +58,6 @@ <h2 id="Controller—post_route">Controller—post route</h2>
       { name: req.body.name }
     );
 
-
     if (!errors.isEmpty()) {
       // There are errors. Render the form again with sanitized values/error messages.
       res.render('genre_form', { title: 'Create Genre', genre: genre, errors: errors.array()});

files/en-us/learn/server-side/express_nodejs/introduction/index.html

@@ -457,7 +457,6 @@ <h3 id="Using_databases">Using databases</h3>
   });
 });
 
-
 //for mongodb version 3.0 and up
 const MongoClient = require('mongodb').MongoClient;
 MongoClient.connect('mongodb://localhost:27017/animals', function(err, client){

files/en-us/learn/server-side/express_nodejs/skeleton_website/index.html

@@ -57,7 +57,6 @@ <h2 id="Using_the_application_generator">Using the application generator</h2>
 
     Usage: express [options] [dir]
 
-
   Options:
 
         --version        output the version number