“While users might think they are bypassing the Great Firewall, they are actually just subjecting themselves to a smaller version of it,” he said.

Just as the Great Firewall was built into China’s internet architecture, so Kuniao, which translates as “cool bird”, constructed a smaller firewall within individual users’ browsers, he said.

That said, it still offered a “wider window” to the internet than other browsers, he said.

“It’s OK for watching YouTube videos,” a person wrote on Weibo, China’s Twitter-like service.

Lee said that while the browser had been given Beijing’s approval – records show Zixun Tech was granted a permit from the Ministry of Industry and Information Technology – they should not think of it as a VPN (virtual private network) as it still screened out sensitive content.

For many years Chinese internet users were able to easily buy and install VPNs – which actually do leapfrog the Great Firewall – but Beijing has steadily tightened its grip on the sector. In 2017, it ordered Apple to remove all such products from its App Store, and in October last year a Shanghai man was sentenced to three years in prison and fined 10,000 yuan (US$1,425) for selling VPN services to several hundred customers without a permit.

On Twitter, several users confirmed Lee’s claim that Kuniao offered only a glimpse of an uncensored cyberspace.

One said he used Kuniao to search for “Falungong” – a spiritual movement that is banned in China and described as an “evil cult” – on Google from behind the Great Firewall but found all of the results it returned were from state media like Xinhua and China Daily.

An equivalent search on Google – using a different browser and from outside the firewall – returned a much wider selection of results, including Wikipedia entries with titles like “Persecution of Falun Gong”, the person said.

According to a now-deleted post on Kuniao’s WeChat account, the browser was launched in September and quickly reached 3,000 users. But the company said that as of Thursday, 200,000 people had either accessed or registered for the service and its servers had been overloaded.

Those who did manage to register for the service were asked to provide a mobile phone number, while the browser’s terms and conditions said that anyone who used it to view content banned in China would have their accounts closed and their browsing records passed to the authorities.

China said to block 23 per cent of accredited foreign news sites

The warning sparked suggestions that Kuniao was actually a trap set by the government.

On Weibo, the top search result for “Kuniao browser” was an image of the product’s name with a trap underneath. The post was liked by almost 2,000 users and attracted 260 comments.

“Who is brave enough to use this? You could be added to a list any minute,” one of them said.

On the popular Pincong forum – which is also blocked in mainland China – a user summed up many people’s views on the new browser.

“No matter how cool it [Kuniao] is, it’s only a bird shut in a cage,” he said.

Zixun Tech did not immediately respond to requests for an interview.