Mozilla plans to overhaul the look and feel of Firefox for Windows, a redesign that will resemble Google's Chrome in several key elements, according to screenshots and discussions on the open source developer's website.

The visual refresh for Windows Vista and Windows 7 will likely take place in two stages. Part of the redesign will land in Firefox 3.7, a minor update now slated to ship in the first half of 2010, while the remaining pieces will wait for Firefox 4.0, a major revision tentatively set for release late next year.

Noting that Firefox's current Windows interface feels "dated and behind," Mozilla wants to spiff up Firefox 3.7 by embracing the "glass" style Microsoft debuted in Vista, moving to a more neutral color palette, hiding the menu bar, trimming the menu to just two items, "Page" and "Tools", and combining "Stop" and "Reload" into one general purpose button.

The decision to hide the menu bar, which Mozilla initially said would be replaced by a "ribbon"-style design similar to the often derided look of Microsoft's Office 2007, raised a ruckus in September when users expressed their displeasure. Mozilla later clarified its planning documents, and denied it would "ribbonise" Firefox.

Firefox 4.0 will continue the interface changes. Current ideas for that 2010 release include giving users the option of moving the browser's tabs to the top of the application's display, a so called "tab on top" look that other browsers, notably Chrome, have adopted.

Other possible interface changes in Firefox 4.0 would combine the browser's address and search bars, another visual element within Chrome, and remove the status bar at the bottom of the display.

The Firefox interface design plans have been spelled out in a long entry on Mozilla's wiki.

Mozilla preempted criticism of some of those moves by saying it is not copying Chrome in particular, or other browsers in general. "We are not trying to make Firefox look like any other browser," Mozilla stated in the planning document. "Firefox is Firefox. Similarities between browsers are unavoidable. They all have shared lineage and are based off of their predecessors. The basics of what a browser does and how it does it is already established. Browsers are all trying to solve the same problems so evolutionary ideas that are similar are inevitable."

Mozilla is also planning to revamp Firefox's interface for its Linux edition in the next two upgrades. The mock ups show some of the same changes as Firefox on Windows, part of Mozilla's plan to make all platforms' interfaces more consistent. In Linux's Firefox 4.0 , for example, the default look may be tabs on top.

Firefox on the Mac is a less pressing interface problem, said Beltzner. "Users are not going to see as much change on the Mac. We'll try to make it fit in as seamlessly as possible with Mac OS X."

One long term possibility for Firefox on the Mac might be to integrate some of the interface elements that Apple recently adopted for its iTunes music software. "As iTunes moves to more of a web-style interface, it's starting to look very different from the rest of OS X," Beltzner added.

Firefox 3.6, which launched last Friday in beta, includes support for some Windows 7 interface elements, including Aero Peek and taskbar thumbnail previews. However, Mozilla dropped support for Windows 7's Jump Lists, a feature that would have listed recently visited sites when Firefox's icon is right clicked in the taskbar, from that version citing development and timing issues.