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LeakZero (https://m.mijisou.com/) is an open source (https://github.com/entropage/mijisou) Chinese meta search engine based on SearX. It emphasizes privacy and doesn't track users as DuckDuckGo. Since it's a meta search engine without ads, LeakZero provides better results than the Baidu, the largest search engine in China. More importantly, it's accessible inside China.
It will be exciting if such a private search engine can be added to Firefox (both on desktop and on mobile), which will definitely protect users in China, where people hardly have privacy towards big companies. Firefox's default search engine in China is Baidu, an infamous company selling people's personal information, advertising dangerous websites at large, and even caused people die (e.g. https://en.wikipedia.org/wiki/Death_of_Wei_Zexi). People are complaining about Firefox's decision to set Baidu as default for a long period. Adding a private search engine will gain Firefox's reputation in China.