NoScript

NoScript is a browser add-on for Mozilla Firefox, which prevents content such as JavaScript, Flash or iFrames to be loaded on websites. It is meant to increase security while surfing and remove the most annoying advertising when loading websites. The term “noscript” has a different meaning in HTML programming. When JavaScript is disabled, the <noscript> or </noscript> tag ensures that a user can still see the contents.

The NoScript add-on

Giorgio Maone developed the NoScript add-on and it was first released for the public in 2005. As of May 2014, it is available in version 2.6.8.23. Since the launch of the browser plug-ins, many bugs have been fixed and its functionality was significantly improved. For example, clickjacking protection and protection against cross-site scripting (XSS) has been optimized. Furthermore, an option has been included to import and export whitelists.

To date, NoScript has been installed more than 2.3 million times (as of May 2015) in Firefox and is one of the most popular extensions for this browser. Many renowned trade magazines and specialist authors recommend the use of NoScript for safer surfing. [1] The NoScript add-on is available on the Mozilla Firefox website for download. Download

Add-On Features

The browser plug-in blocks by default the following when loading the content of a website:

  • JavaScript
  • Java applets
  • Microsoft Silverlight
  • Adobe Flash

and protects against:

  • Cross-site scripting
  • Clickjacking

As an option, you can also block frames and iframes.

Benefit for users

For private Firefox users, the NoScript add-on is recommended as it may prevent harmful functions from running. Anyone who works daily with Firefox, for example, as an SEO specialist, must keep in mind that a lot of features won’t be able to be checked “live” when using NoScript. JavaScript functions, for example, cannot be tested when NoScript is enabled.

The noscript tag

The so-called noscript tag can be inserted both in the <head>- or <body>- section of an HTML document. It contains content that is displayed by a browser that has JavaScript disabled, or cannot read those elements. The <noscript>- usually contains simple text.

Functioning and implementation of noscript tags

<noscript> is placed at the beginning of the applicable section and <noscript/> at the end. Single block elements can be inserted with headings or
between these two elements. The browser can then display that as an alternative. It is important in implementation that the content of the <noscript> area contains the content of the JavaScript application or provides information on what to expect there if JavaScript is activated. If JavaScript is used for a website’s menus, for example, the link targets should be listed between the noscript elements.
<script type="text/javascript"><!-- // /*
  /* <![CDATA[ */
	document.write("<p>| <a href='#'>Home</a> ");
	document.write("| <a href='#'>News</a> ");
	document.write("| <a href='#'>Category1</a> ");
	document.write("|</p>");
  /* > */
 </script>
    	<noscript>
  <p>|  <a href="#">Home</a>  |  <a href="#">News</a>  |  <a href="#"> Category1</a>  |</p>
 </noscript>

Benefit for SEO

For a long time the noscript element was used by SEOs to write additional content in the source code of a website. Sometimes, large amounts of text were used to manipulate the ranking in search engines effectively. But Google has recently officially confirmed that the bots can also read JavaScript and Flash. [2] Every SEO should be aware of the fact that the above described methods are classified as webspam and such actions inevitably lead to penalties, ranking losses or exclusions from the index.

References

  1. References on the NoScript home page noscript.net Accessed on 05/14/2014
  2. Crawling through HTML-Forms googlewebmastercentral.blogspot.com Accessed on 05/15/2014

Weblinks

On the NoScript plugin:

On the noscript tag:

Category

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