K-Meleon is a free and open-source, lightweight web browser for Microsoft Windows. It uses the native Windows API to create its user interface. Early versions of K-Meleon rendered web pages with Gecko, Mozilla's browser layout engine, which Mozilla's browser Firefox and its email client Thunderbird also use. Current versions of K-Meleon use the Goanna layout engine, a fork of Gecko created for the browser Pale Moon. K-Meleon became a popular Windows browser and was available as an optional default browser in Europe via BrowserChoice.eu.
K-Meleon began with the goal of being faster and lighter than Mozilla's original Internet suite. Until 2011, K-Meleon embedded Gecko in a stripped-down interface. Throughout its lifespan, K-Meleon has required small amounts of random-access memory (RAM). K-Meleon 76 supports discontinued versions of Windows such as Windows XP and Windows Vista. Mozilla no longer supports these platforms after their Firefox Quantum rewrite.
Customization is another primary design goal. Users can change the toolbars, menus, and keyboard shortcuts from text-based configuration files. K-Meleon supports macros, which are small browser extensions that users can examine, write, or edit in a text editor. K-Meleon's custom configuration files can trigger macros. Reviews describe the customization features as versatile but intimidating to the average user. Due to its adaptability, K-Meleon was recommended for Internet cafés and libraries in the early 2000s.
History
Christophe Thibault started the K-Meleon project in the 2000s, when many new browsers were launched. To open-source their once-dominant Netscape Communicator Internet suite, Netscape founded the Mozilla project. K-Meleon was one of several browsers to use Mozilla's browser engine Gecko. Thibault designed K-Meleon to combine Gecko with native Windows interface elements, an approach that was less resource-intensive and allowed the browser to blend into its environment.
Embedding Gecko
alt=Screenshot of K-Meleon with a right-click menu|thumb|left|K-Meleon 0.2
Christophe Thibault released K-Meleon 0.1 on August 21, 2000. Thibault said he created the first simple release to attract attention, during a day off.
Thibault handed the project over to new developers, including Brian Harris, Sebastian Spaeth, Jeff Doozan, and Ulf Erikson, who began implementing browser functions through modular Kplugins. The K-Meleon team released new versions with pop-up blocking and cookie management. These releases introduced text-based configuration files called configs that allowed users to customize the browser or hide interface elements, To create a stand-alone browser, the Galeon project embedded Mozilla's rendering engine. Galeon was released for Linux using GNOME's widget toolkit GTK. K-Meleon brought a similar approach to Windows using the operating system's native application programming interface (API) to create a lightweight user interface (UI). Mozilla created user interfaces via their cross-platform XML User Interface Language (XUL) layer. This technology used Gecko to lay out application interfaces. K-Meleon was smaller and more closely integrated into the Windows desktop than Mozilla's browser, and could use the native bookmarking system to access Internet Explorer's favorites.
In Europe, version 1.5 was an optional default Windows browser through Microsoft's browser ballot. Due to accusations of abusing its market position to promote Internet Explorer, Microsoft introduced a browser ballot in the European Economic Area (EEA). By 2010, it offered Windows users a choice of the 12 most popular web browsers, including K-Meleon.
7x releases
In 2011, Mozilla ended support for embedding the Gecko layout engine; because K-Meleon had previously relied on this API, the browser's future became uncertain. In 2013, after years without an official, stable release, the K-Meleon group began developing version 74. XULRunner was a stand-alone implementation of the Gecko engine designed to launch applications. K-Meleon 74 used XULRunner instead of Mozilla's deprecated embedding software.
K-Meleon 75 included a spelling checker, form auto-completion, and a new skin system. Boissonnade began work on version 76 but suffered a hard disk drive failure during beta testing.
Goanna branch
thumb|alt=Two screenshots of K-Meleon with different appearances drawn from the windows theme|Two screenshots of K-Meleon 76 with the same K-Meleon theme but different system themes
Active development on K-Meleon takes place using Goanna, a fork of Gecko created for the browser Pale Moon. With Firefox Quantum, Mozilla rewrote large parts of its browser engine. In 2017, Roy Tam forked K-Meleon 76 to run on Goanna. The project's former lead developer Boissonnade wrote; "Thanks for taking care of that little lizard [after I] left it". K-Meleon on Goanna remains compatible with deprecated versions of Windows and can run with smaller amounts of RAM than those required by mainstream web browsers. K-Meleon has lower memory requirements than other low-resource browsers.
K-Meleon is updated on a rolling release schedule. By default, the browser is a multi-lingual portable application that can directly run from the host computer or removable media. It is also included in the PortableApps.com repository. By 2023, K-Meleon was not compatible with major web apps and social media sites. As of October 2024, the final planned release is version 76.5.5. These configs can call upon macros,
<syntaxhighlight lang="apache">
HelloWorld{
alert("Hello world!");
}
</syntaxhighlight>
To trigger the macro, a keyboard accelerator could be created by adding the code below to the accelerator config, causing the macro to launch if the <kbd>Ctrl</kbd>, <kbd>Alt</kbd>, and <kbd>H</kbd> keys are pressed at the same time.
<syntaxhighlight lang="clojurescript">
CTRL ALT H = macros(HelloWorld)
</syntaxhighlight>
Custom toolbars offer more options, but the syntax is similar. The example below would create a new toolbar with a button to trigger a macro.
<syntaxhighlight lang="Apache">
NewToolbar{
!NewButton{
macros(HelloWorld)
}
}
</syntaxhighlight>
This combination of configs and macro modules provides control over much of the browser. It also creates a learning curve for customization that is not present in most browsers. A CNET review criticized K-Meleon because it "requires some knowledge of computer code to get the most out of it". Popular browsers use systems like WebExtensions, where there is a separation between users and extension developers.
Because of its flexibility, K-Meleon was useful for environments in which the browser needed to be customized for public use, such as libraries and Internet cafés. It allowed administrators to hide some features from patrons. For example, a library could hide interface elements like the address bar or limit the computer's access to an online resource like the library catalog.
Legacy Windows versions
K-Meleon supports a range of legacy software and hardware. Windows XP and its Windows Embedded POSReady 2009 variant have been unsupported since 2019. The latest major browser releases to support these operating systems are Microsoft's Internet Explorer 8 (2014), Google Chrome 49.0.2623.112 (2016), and Mozilla Firefox 52.9.0 (2018).
Web browsers cannot access secure websites if they do not support Transport Layer Security (TLS) encryption. As of 2018, most major web sites use TLS encryption via HTTPS. Early versions of K-Meleon for Windows 2000 and Windows 9X receive occasional updates for TLS certificates. K-Meleon 1.5 can run on Windows 95, Windows 98, and Windows Me. Occasional TLS updates allow version 1.5 to access secure websites.
Release history
K-Meleon, which was first released in 2000, has been under development for over 20 years and is still maintained. The most-recent version K-Meleon 76 is updated on a rolling release schedule. All versions of K-Meleon are written for Microsoft Windows operating systems.
