Mozilla Labs has become the latest developer to float a new prototype user interface for PCs, the Webian Shell, which reinvents the web browser as a complete replacement for the desktop.

Based on the Chromeless Browser project's fusion of HTML, CSS and Javascript, Webian is in essence a browser window that has taken over the PC, with an address bar at the top of the window, tabs for web applications, and a clock.

Despite its currently primitive appearance, the concept shows the influence of smartphone and tablet operating systems by aspiring in future versions to enable multiple homescreens, split screens and on-screen keyboard, which suggests that it would require a touch interface.

What is missing from release 0.1 is any form of integration with an underlying operating system - Linux of course - but perhaps as a concept that is the point. Webian could sit on top of any distribution, depending on what it was being used for.

"If you find most of the stuff you do on your PC these days happens in a web browser then you might find that the desktop environment you used to depend on is now just getting in your way," says the introduction on the Webian blog.

"The idea of the Webian Shell project is to replace your computer's interface with something much simpler, which treats web applications as first class citizens and does away with all the un-necessary clutter."

Although not a full web-oriented operating system in the mould of the somewhat similar Google Chrome OS, Webian does hint at a distinct vision of what operating systems might turn into.

According to Microsoft with its smartphone-like Windows 8, trailed heavily last week, an operating system is an interface bonded to a proprietary underpinning that runs much as Windows always has, full of legacy code, assuring compatibility with old software and consuming considerable resources.

According to snipers, the struggle with this model will be satisfying both audiences; those wanting a keyboard-driven interface designed to interact with large number of complex, local applications, and the remainder that would be happier with a streamlined smartphone or tablet look and feel.

Linux, meanwhile, has a number of distributions, young and not to young, more than one interface scheme - including the controversial Unity now used on Debian descendant Ubuntu. One path is for the interface and the operating system to become two entities, chosen separately, at least for open source operating systems. Webian is perhaps one path to establishing that idea as credible and practical.

Developers can check out Webian Shell on the project website.