This article originally appeared on ABACUS China’s Great Firewall is known to frustrate the country’s internet users by blocking many of the world’s most popular websites. So when one company offered what it called a legal way to hop the wall, many netizens pounced on the opportunity. The story of China’s Great Firewall, the world’s most sophisticated censorship system Kuniao, which means “cool bird,” is a new browser marketed as China’s first legal tool to allow visits to “popular foreign websites,” including Twitter, Facebook, YouTube, Google, Reddit and Instagram. The company says it provides “cross-border professionals” with a fast and steady service to help users “go overseas.” In a Weibo post , the company said it serves the cross-border ecommerce industry. But anyone who can manage to get an invitation code to sign up for the browser can use it. As a result, it’s been gaining traction on social media. The browser works by having users connect to a “special network.” Kuniao says it doesn’t change a user’s IP address and it’s not advertised as a VPN or proxy, but the mobile app will show you connected to a VPN through one of two servers in Hong Kong. This isn’t an anti-censorship tool, though. Twitter users noted that the browser censors Google search results for sensitive words, including June 4, Falun Gong and Xi Jinping. And a notice to users in the Kuniao iOS app explicitly says “actively browsing content that violates the ‘ seven base lines ’ and ‘ the prohibited nine ,’” two principles concerning online censorship, will get users’ accounts banned. The notice also says the company will submit “illegal behaviors” and “browsing records” to relevant authorities. The program’s newfound popularity has apparently been too much for its servers, as service either doesn’t work or has slowed to a crawl. Some users in a Kuniao WeChat group complained that websites won’t load or are extremely slow, but others said they were able to visit some foreign websites like YouTube. According to a now-deleted post on Kuniao’s WeChat account, the app was originally launched back in September and quickly reached 3,000 users. By November 14, the company said the servers were overloaded with 200,000 people having either accessed or registered for the service. The company attributed this to two popular Weibo users posting about the browser. In its customer service WeChat group, a Kuniao staff member said the company now has more than a hundred WeChat groups passing out invitation codes. (WeChat groups can hold a maximum of 500 people each.) A Weibo hashtag about the browser calling it “China’s first legal commercial VPN” drew more than 12 million views, but posts with the hashtag currently can’t be seen. We haven’t been able to verify the company’s claim that the browser “complies with laws and regulations.” The developer of the browser is a Fuzhou-based company named Zixun, according to a WeChat post. We reached out to Zixun and were referred to a representative for the browser, but calls to the representative went unanswered. Zixun says its business involves big data mining, technology services, and the development and sales of software and hardware. The company has also made three other products that are all ecommerce tools for businesses. In China, unauthorized VPN services are illegal , and some VPN users have been fined in the past. The country’s rules for online censorship are also murky and periodically tightened. But unlike other VPN services, Kuniao’s still appears to censor search results. It may not be the same as the unfiltered Web seen in the West, but Kuniao seems to take Chinese netizens a step closer to discovering a whole world of sites on the other side of the Great Firewall. For more insights into China tech, sign up for our tech newsletters , subscribe to our award-winning Inside China Tech podcast , and download the comprehensive 2019 China Internet Report . Also roam China Tech City , an award-winning interactive digital map at our sister site Abacus .