Europeans are not getting as wide a choice of browser as they may think, claims a web designer.
From 1 March, European users of Microsoft's Internet Explorer began seeing pop-up screens asking them if they wanted to try a different browser.
The choice was offered to settle an anti-trust case the European Commission brought against Microsoft.
But some say almost half the browsers on offer are clones of IE that only give people an illusion of choice.
When the browser choice page popped-up for web designer Richard Quick, he decided to try out some of the lesser known programs on offer.
While installing and using them he noticed that many were based around a core technology, known as a rendering engine, built and maintained by Microsoft. The firm's Internet Explorer (IE) uses the Trident engine.
IE and four of the other less well-known browsers, Avant, Maxthon, Slim and Green Browser, all use it too. Another, Sleipnir, uses Trident as a default and can also use the Gecko rendering engine.
"The aspect of a browser that decides what bit to put where on the page, that's the rendering engine," said Mr Quick.
While he acknowledged that most people were likely to pick one of the popular programs shown on the first browser choice page - which include Apple's Safari, Google's Chrome, Mozilla's Firefox and Opera - his complaint is that those who pick a new one were not getting as much choice as they thought.
Of the 12 browsers on offer, five use the Trident rendering engine, three use Mozilla's Gecko, two use WebKit, and one uses Opera's Presto. Sleipnir can use either Trident or Gecko.
This meant, he said, that almost half of the browsers being offered were IE or something very similar.
"If you choose IE you will get pages rendered the IE way," he said. "But if you choose these browsers you will get the pages rendered the IE way too."
Mr Quick said he had sent a complaint about the choices to the European Commission.
A Microsoft spokesman declined to comment on Mr Quick's findings but directed the BBC towards public documents which set out how the choice of browsers was made.
Clause 10 of this said: "Nothing in the design and implementation of the Choice Screen and the presentation of competing web browsers will express a bias for Internet Explorer."
Microsoft is also not allowed to feature any browser "which is based on Internet Explorer's rendering engine and the development or distribution of which is funded in whole or in substantial part by Microsoft."
The browser choices, it said, is based on the 12 most widely used browsers that run on Windows 7 measured by an agreed methodology.
Another web designer Paul Boag said few web designers were fans of the Trident rendering engine.
"From a web designers point of view, its all to do with support for the World Wide Web Consortium specifications," he said.
These specifications dictate how the different elements of a webpage should be displayed. Mr Boag said Chrome, Safari, Firefox and Opera did the best job of adhering to the W3C specifications.
"Internet Explorer is somewhere down the list," he said.
This meant, he said, that many of the things it was easy to do in other browsers, such as create shadows on the page, required far more lines of code or workarounds in IE.
There is currently a vocal campaign to extinguish the older IE version 6. Mr Boag said this had largely come about because its rendering engine was so out of date and hard to use.
Many web designers were now pushing a technology called "progressive enhancement" said Mr Boag.
This tunes a webpage to the software that people use to view it, he said.
"It gives the less intelligent browser something much more basic and gives the better browser something better on top," he said.
If it was widely adopted, he said, it could mean that users of IE or browsers that use the same rendering engine see only the most basic elements of a page. Others with more sophisticated browsers will get the full experience.