Jaslabs: High performance Software

by Justin Silverton

For most web applications, there are a couple of different options available for storing data on the client (within the web browser).

Flash allows the storage of up to 100 KB/domain without any user security prompts. The data being stored is accessible across the user’s Flash Player instances, loading stored data into Internet Explorer, Firefox, or any other browser that supports it.

Cookies are another option. A cookie stores user data across multiple browsing sessions. They are limited to 4 KB of storage per domain and are a good way to store user data for convenience or tracking. Web browsers contain cookie and privacy management features to wipe away stored cookies and their stored data and therefore have limited utility for continued persistence. Cookies are sent along with every request on a given domain, adding onto every message exchanged between an end-user’s browser and your site, even if the cookie data is only occasionally used.

Firefox has the ability to store an unlimited amount of data using DOM storage (This may be limited in future versions greater than 2.X).

Here is an example of how use DOM storage:

<script type="text/javascript">

//for security, this must be set to your domain
var storage = globalStorage['yourdomain.com'];
var pageCount;

function setItem(key,value) { //store an item
storage.setItem(key,value);
}

function getItem(key) { //retrieve an item and display it
alert(storage.getItem(key));
}

function removeItem(key) { //remove an item
storage.removeItem(key)
alert("Key:" +key +" was removed.");
}
</script>


Here are some other options that can be used with the globalStorage object:

• globalStorage[’developer.mozilla.org’] - All web pages within the developer.mozilla.org sub-domain can both read and write data to this storage object.
• globalStorage[’mozilla.org’] - All web pages with the mozilla.org domain can both read and write to this storage object.

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By Justin Silverton

The following are 5 Firefox extensions that will extend tab functionality.

1) IE tabs

This is a great tool for web developers that allows you to view web pages in Internet Explorer within a firefox tab.

Download Here

2) Informational tab

This extension provides thumbnail-style preview for each tab, does progress meter, and indicates unread status.

Download Here

3) Tab Mix Plus

Tab Mix Plus enhances Firefox’s tab browsing capabilities. It includes such features as duplicating tabs, controlling tab focus, tab clicking options, undo closed tabs and windows, plus much more. It also includes a full-featured session manager with crash recovery that can save and restore combinations of opened tabs and windows.

Download Here

4) TabSidebar

Features:

• Provides navigation options for each tab including history, stop and reload.
• Allows you to move tabs around with drag and drop.
• You can drop links, local files and bookmarks anywhere you like in the tab list.
• Displays the security status of tabs.
• Automatically refreshes the tab preview whenever the page changes.
• Lets you hide the main tab bar when the sidebar is open.
• Bidirectional support making the sidebar work correctly in right-to-left languages.
• Works well with other tab-related extensions allowing you to use their context menu additions from the sidebar.

Download Here

5) Tab Effect

This adds a tab switching cube effect to Firefox.

Download Here

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By Justin Silverton

The following are the top 5 firefox extensions that every developer should be using.

5) Open source in tab

Opens the page’s source file in a new tab. Has a preference to either open source in a new tab or existing tab.

Download here

4) IE Tab

A great extension that allows you to run an instance of Internet Explorer in a firefox tab. This is great for testing a new site that may look different in each browser.

Features:

• Supports multiple languages
• Allows the switching of the rendering engines (IE and mozilla) with one click

Download here

3) Server Switcher

Server Switcher allows you to easily switch between sites on your development and live servers, so that you can immediately see the differences.

Features:

• You can create multiple development/live-server-pairs.
• Multiple keyboard shortcuts
• Support for ports other than 80
• supported by flock and firefox

Download here

2) Web Developer

The sheer number of options and developer tools that are available with this plugin make it a great option for a web 2.0 environment.

Features:

• Easily disable java, javascript, popup blocker, and referrers.
• View Advanced cookie information
• Advanced form debugging - (Show passwords,convert GET <=> POST,remove maximum length)
• Outline frames, headings, links, and tables
• Resize the current window
• Validate CSS,HTML,Links, and WAI

Download Here

1) Firebug

Any list involving firefox plugins and developers should have firebug near the top. This plugin is great for debugging javascript in realtime, which is a must for anyone developing a web application.

Features:

• Inspect and edit HTML live on any website.
• Measure all the offsets, margins, borders, padding, and sizes (great for CSS).
• Get a list of each individual javascript file that is being loaded and each load time.
• Pause javascript execution and set breakpoints.
• Advanced javascript, CSS, and XML error reports
• Edit DOM objects in real-time
• Javascript command-line for easy execution of code

Download Here

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By Justin Silverton

In a recent article, a new flaw in firefox 2 is discussed:

“Mozilla’s Firefox 2.0 has long been considered a safer Web browser than Microsoft’s Internet Explorer, but a new flaw in the Firefox Password Manager, which lets users store usernames and passwords for trusted Web sites, could let hackers steal their login data.

The problem, known as a reverse cross-site request, or RCSR, was first discovered by Robert Chapin, a Microsoft Certified Systems Engineer (MCSE) and I.T, consultant. The RCSR appears on blogs, message boards, or group forums that let users add comments with embedded HTML code.

On sites that allow users to enter code, a hacker can embed a form that tricks the user’s browser into sending its username and password information to the hacker’s computer. Because the form is embedded on a trusted Web site, the browser’s built-in antiphishing protection, which is designed to alert users to fraudulent Web sites, does not detect the problem.”

When will this flaw be fixed?

The Mozilla Foundation (the group behind the firefox browser) has classified it as Bug #360493 and also announced that it will be fixed in version 2.0.0.1 or 2.0.0.2.

This attack can be avoided by disabling the browsers’ autosave features for usernames and passwords. In Firefox, the feature is found in the “Options” window under the “Tools” menu.

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