K-Meleon

K-Meleon is a free and open-source, lightweight web browser for Microsoft Windows. Unlike cross-platform browsers, it uses the native Windows API to create its user interface. K-Meleon can use the secure Goanna layout engine based on Mozilla's Gecko or the Gecko engine itself. K-Meleon began with the goal of being faster and lighter than Mozilla's original internet suite. It still has lower system requirements than most browsers and supports legacy software and hardware including pre- SSE processors, Windows XP, and Windows Vista.

Customization is another primary design goal of K-Meleon. In addition to extensions, K-Meleon also supports text-based configuration files and macros that allow end-users to customize every aspect of the interface. Due to its configurability, K-Meleon was previously recommended for public-facing computers like those in internet cafes and libraries.

History

Christophe Thibault started the K-Meleon project in the early 2000s. During that time, more of the web was made of static web pages and less was composed of web apps. Many projects formed to create new browsers. K-Meleon was one of several browsers built around Mozilla's embedded Gecko web engine. The Mozilla Application Suite used Gecko to both render pages and also create graphical interface elements like toolbars and menus. Christophe Thibault designed K-Meleon to combine Gecko with native Windows interface elements. This approach was less resource-intensive and allowed the browser to blend into its environment. In Thibault's native French, the letter "K" in the browser's name would be pronounced the same as the first syllable in ''caméléon'', the French term for a chameleon.

Embedding Gecko

Christophe Thibault released K-Meleon 0.1 on August 21, 2000. While working at Nullsoft, Thibault created the first release during a single day off. He began by building and branding Mozilla's test application for embedding the Gecko layout engine. K-Meleon 0.1 was simple but quickly attracted attention to the project. For the 0.2 release, Thibault implemented many expected features including context menus, and he moved development to SourceForge to welcome contributors.

K-Meleon was built with open-source code from Mozilla but offered a few key advantages over the Mozilla Application Suite. The suite bundled additional components beyond a web browser including email, news, chat, and webpage editing. The Galeon project created a lightweight, standalone browser by embedding Mozilla's rendering engine. However, Galeon was only available on Linux as it used GNOME's widget toolkit, GTK. K-Meleon brought a similar approach to Windows, releasing a standalone Gecko web browser two years before the Firefox alpha release. K-Meleon also used the native Windows application programming interface (API) to create its user interface which lightened the browser. Mozilla used the Gecko rendering engine to render the browser's interface via their cross-platform XML User Interface Language (XUL) layer. XUL allowed Mozilla to build one application for several operating systems, but it increased the size of the application and by design generated graphical controls that did not match the rest of the system. K-Meleon required less memory, was integrated into the look and feel of the Windows desktop, and could even use Microsoft's own bookmarking system to directly access Internet Explorer's favorites. The approach that Galeon had taken on the GNOME desktop and K-Meleon had taken on Windows was later used by Camino on macOS.

Mozilla programmers cited the existing stand-alone browsers K-Meleon, Galeon, and Camino when they began developing Firefox, and Mozilla publicly referred to K-Meleon in Firefox's initial alpha release. Dave Hyatt was a founding developer for Safari, Firefox, and Camino. Hyatt criticized Mozilla and Netscape's work on the internet suite in contrast to focused browser projects. He stated, "You don't see Galeon UI designers trying to co-develop their UI with the rest of the world, nor do you see that with ..K-Meleon." During the time that Mozilla maintained an embeddable Gecko engine, they showcased several stand-alone browsers including K-Meleon as examples of the embedding technology.

Thibault welcomed contributors to K-Meleon and handed the project over to new developers Sebastian Spaeth, Brian Harris, Jeff Doozan, and Ulf Erikson. Within a year, new contributors had moved browser functions into a modular system of compiled libraries called Kplugins. The K-Meleon team released several new versions of the browser to fix bugs, improve stability, and add features like pop-up blocking, cookie management, encrypted downloading of web pages via SSL, and online proxies for anonymity or content filtering. The developers introduced text-based configuration files or configs. The config files provided a way to fully customize the browser's interface and hide interface elements on publicly accessible computers. The developers also created a unique macro language to customize the browser. In K-Meleon, macros are a smaller type of browser extension designed to be human-readable and modified or created by end-users.

By October 2002, K-Meleon 0.7 included many of the browser's core features and rendered pages with the Mozilla 1.0 engine. Version 0.7 implemented skins to theme the browser's appearance. It also provided support for Netscape Plugin Application Programming Interface (NPAPI) plugins. NPAPI plugins, also known as third-party plugins or just plugins, were a de facto industry standard for embedding media and interactive content in web pages. Ulf Erikson implemented tabbed browsing functionality with his optional "layers" feature. Layers provided the functionality of tabbed browsing and worked with other K-Meleon features including macros and mouse gestures. Layers, however, on an API level implemented tabs as separate stacked windows. As a side effect, the operating system would repaint the window and perform the animation for opening a new window each time a different tab was selected. Despite the disbanding of upstream parent company Netscape in 2003, K-Meleon experienced a relatively stable year. Mozilla continued work on Gecko, and K-Meleon itself was refined with service packs and the incremental 0.8 release.

In 2005, Ulf Erickson announced that version 0.9 would be the final version he would build. He was the project's developer but stated that he was no longer using K-Meleon as his primary browser after moving to Linux. In January 2006, Dorian Boissonnade became the lead developer and began working towards a 1.0 release.

Boissonnade had co-developed an unofficial build of K-Meleon with Hao Jiang for the Chinese-language Classic Club Forum (CCF) before becoming an official developer. They brought several features first introduced in K-Meleon CCF to the official releases, including an improved localization system. Released in July 2006, K-Meleon 1.0 made the browser fully translatable. Previous versions could be translated because they were open-source. The source code could be downloaded, the source files could be translated, and the browser code recompiled. Version 1.0 stored localizations in separate library files within existing K-Meleon installations. The layout engine was also updated to the latest Gecko release from Mozilla. This brought improvements to security and usability, including support for favicons, a flexible search engine system, and better support for multi-user environments. K-Meleon maintained support for its existing system of text-based configuration files and introduced a new graphical interface to change many preferences from within the browser.

Version 1.1 expanded the macro system. Earlier versions placed all of the macros into a single config file. Initial releases came with under 50 lines of macro code and instructions for end users to create their own macros. Subsequent versions each came with more lines of macro code and many users wrote and shared macros. By 2008, users were sharing macros as an alternative to the add-ons for Mozilla Firefox. To make the macros more manageable, K-Meleon developers separated them into module files. The modules could be more easily shared, downloaded, and edited. All K-Meleon versions released since have retained compatibility for this system. Macro modules, skins, and configuration files were also split into a default stored in the browser's folder, and customizations stored in a user's profile as part of the transition to a multi-user design.

Version 1.5 introduced a true tabbed interface. Earlier versions relied on the optional "layers" plugin. That had limitations like repainting the entire window when switching tabs. First introduced in the unofficial K-Meleon CCF, true tabs supported drag and drop, could have individual close icons, could be placed on the bottom of the window, and sets of tabs could be restored as a session when restarting the browser.

In 2009, Microsoft struck a deal with the European Commission. To resolve accusations from Opera that it was abusing its market position to push Internet Explorer, Microsoft introduced a browser ballot. Beginning in 2010, Microsoft was required to offer Windows users in the European Economic Area a choice of the 12 most popular web browsers including Microsoft's Internet Explorer, Mozilla Firefox, Google Chrome, Opera, K-Meleon, and several others. Shortly after the ballot was released, K-Meleon official downloads peaked near two hundred thousand per month. Other browsers saw an even greater increase. Opera reported a three-fold increase in user base. Six of the less popular browsers filed a second complaint against Microsoft. Microsoft's ballot design initially showed the 5 browsers that were at least as popular as Opera and did not show the remaining 7 browsers unless users clicked a horizontal scrollbar. Shawn Hardin, CEO of Flock, alleged that the ballot did not provide European consumers with the required choice between the 12 most widely used web browsers, but rather limited it to an "oligopoly for five" large projects.

7x releases

In 2011, Mozilla dropped support for embedding the Gecko layout engine. As K-Meleon had previously relied on this API to combine Mozilla's display engine with its native Windows interface, this left the future of the browser uncertain. Mozilla's change resulted in the end of the Camino web browser which embedded Gecko within a native interface for Mac OS X. The Camino developers initially explored transitioning to the Webkit rendering engine. When the Webkit transition did not work, the developers discontinued to the Mac-only browser altogether. Marco Gritti, the lead developer of Galeon had already forked that project to create GNOME Web and switched to a WebKit backend. GNOME developer Christian Persch described Mozilla's support for embedding Gecko on Linux as, "unmaintained and stagnant."

After years without an official, stable release, the K-Meleon group released version 74 in 2014. While Mozilla had ended support for embedding Gecko, they still maintained a technology called XULRunner. XULRunner was a standalone implementation of the Gecko engine designed to launch cross-platform applications. K-Meleon 74 was the first official release to use XULRunner instead of Mozilla's deprecated embedding software. Outside of the new engine, version 74 brought small improvements including a new default theme, better CPU usage, and minor bug fixes. This was the final version to support Windows 2000 and therefore still received occasional updates.

K-Meleon 75 was released in 2015 with a Mozilla 31 backend, Transport Layer Security (TLS) 1.2 support, a new skin system, a new toolbar implementation, spellcheck, and form auto-completion. Prior to version 75, buttons were defined in pixel size by their skin or theme. For high-resolution monitors, this could result in either tiny icons or a blurry up-scaled browser. Version 75 introduced a skin system that allowed end users to adjust the icon size, and would automatically adjust the default icon size to a degree. K-Meleon 75 also expanded and included the previously optional Kplugin, JSBridge. JSBridge offered partial support for Mozilla-style add-ons. A few Mozilla add-ons like NewsFox and Cookie Keeper took advantage of it but were not direct ports. Yvon Tanguy, the developer of Cookie Keeper, commented that "the only way efound to perform" a crucial routine on K-Meleon was to include "cookiekeeper.kmm", a small file that users would have to manually extract. Boissonnade began work on version 76 but suffered a disk failure during beta testing.

Goanna branch

Since 2017, all active development on K-Meleon has taken place using a fork of the Goanna engine. With Firefox Quantum, Mozilla rewrote most of the Gecko engine from the ground up. The Goanna engine is a maintained fork of the pre-Quantum Gecko engine created by Pale Moon developers.

Roytam forked the most recent version of K-Meleon in 2017 to run on the Goanna engine. The project's lead developer, Boissonnade, expressed enthusiasm and approval of this new branch but stepped away from the project without formally transferring control or ownership. Goanna is actively developed but has not fully implemented recent web features introduced by Google like Shadow DOM. Shadow DOM was originally released by Google as a non-standard feature in Chrome. The implementation in Goanna is incomplete and disabled by default.

K-Meleon also does not support the online Digital Rights Management (DRM) introduced in 2017. The Free Software Foundation (FSF) criticized the World Wide Web Consortium for including DRM in the web's specification as antithetical to free and open-source software. FSF executive director John Sullivan responded to the standardization of DRM by saying, "We're mourning the Web." Larger free software projects including Kodi and Firefox have handled the incompatibility of DRM and free software by signing an agreement with Google to side-load their proprietary Widevine DRM implementation. Many smaller projects like GNOME Web, Basilisk, K-Meleon, and the aborted Metastream project have been unable to support these proprietary encryption methods.

K-Meleon on Goanna is updated on a weekly rolling release schedule. By default, the browser is a multi-lingual portable application that can run directly from the host computer or removable media. As a fork from the official release chain, K-Meleon will not update automatically; it can be manually updated. It is also included in the PortableApps.com repository.

Customization

Every component of K-Meleon's interface can be controlled by the end user or system administrator. Many features can be controlled from the graphical user interface. Toolbars can be enabled, disabled, or positioned from the browser window. Many settings can be adjusted from a preferences panel. Deeper customization is possible using text-format configuration files, or configs. The menus, keyboard shortcuts, icons, toolbars, and buttons can all be customized via K-Meleon's configuration files. These configuration files can, in turn, call upon macros. K-Meleon's macros are a type of small extension that can also be opened in a text editor by end users.

A simple "Hello, World!" program could be written in K-Meleon's macro language as below:

NewMacro

A user or administrator could add a button to trigger the macro above by adding the code below to their toolbar configuration file:

!HelloWorld

This combination of configuration files and macro modules provides users a greater degree of flexibility than in other browsers. It also creates a learning curve for customization that is not present in most browsers. Popular browsers rely on systems like WebExtensions for customization where there is a distinct divide between end users and extension developers. K-Meleon does support several types of extensions including simple macro modules, C++ plugins called Kplugins, and XUL-based extensions similar to but not compatible with those previously used by other Mozilla applications.

However, K-Meleon never had a community of extension developers comparable to those of Firefox or Chrome. The most popular browser in 2020 was Google Chrome which had over 130,000 WebExtensions available for download. Mozilla Firefox supported XUL-based extensions until 2018. When the Classic Adds-Ons Archive preserved the add-ons for Firefox in 2017, there were over 16,000 available. In contrast K-Meleon never had more than a few hundred extension developers, despite support for a small number of major extensions like AdBlock Plus.

K-Meleon's flexibility was a reason that it was recommended in the early 2000s for environments where the browser needed to be customized for general public use, such as libraries and internet cafés. It allowed an administrator to create a custom browser interface for patrons, save this interface in the file system, and then distribute the interface to all public-facing computers. In the mid-2010s, libraries shifted to more enterprise cloud-based solutions, and internet cafes dwindled with the increased use of mobile computing devices.

Legacy Windows versions

K-Meleon supports legacy versions of Windows that other browser vendors have abandoned. The current version supports Windows XP, Windows Server 2003, and Windows Vista. The latest major browser releases to support these platforms are Microsoft's Internet Explorer 8 from 2014, Google Chrome 50 from 2016, and Mozilla Firefox 52 from 2018. The only other browsers to provide updates to these operating systems are unofficial ports like the Firefox-based Mypal.

Even older versions of Windows receive some updates. Web browsers for Windows 2000, Windows NT, and Windows 98 cannot access most modern websites if they do not support TLS encryption. When TLS 1.2 was released in 2008, major browser vendors were no longer targeting Windows 2000 or earlier. HTTPS was initially used for only sensitive data transfers like banking. However, by 2018 the majority of web pages used TLS encryption.

K-Meleon 74 can access secure websites on Windows 2000 using an older version of the Goanna engine combined with up-to-date ciphers. It provides both TLS 1.2 for access to HTTPS sites and greater web compatibility than other web browsers released for the OS. K-Meleon 1.5 can access secure websites on Windows 98 using TLS patches. However, there are no updates available for K-Meleon 1.5's web engine.

Release history

All versions of K-Meleon are written for the Microsoft Windows operating system. All versions support 32-bit and pre- SSE processors. All versions support Windows XP and Vista. Version 74 is the latest version to support Windows 2000. Version 1.5.4 is the latest stable release to support Windows 98. K-Meleon is not designed for Unix, but can run on POSIX-compliant systems if they have an implementation of the Windows API like the Wine compatibility layer.

References: K-Meleon file releases, release notes, changelogs, and the Announcements forum.

See also

* Comparison of feed aggregators
* Comparison of lightweight web browsers
* Comparison of web browsers
* List of feed aggregators
* List of web browsers

References

Several free and open-source projects referenced in this article have gone by multiple names. The following may be referred to by previous official names or internal codenames in the cited references:

{{Web browsers, desktop

2000 software
Free web browsers
Gecko-based software
Gopher clients
News aggregator software
Portable software
Web browsers based on Firefox
Windows-only free software
Windows web browsers