I guess that's what i dont understand, what are the needs of the people in this market and what about chrome or firefox fails to meet that need? It doesn't have flexbox support, and i would imagine that would break a ton of modern websites. It isn't like these markets have their own version of html/css, everyone's on the same web, so why go for a browser with worse support for modern standards?
Users don't know/care about flexbox at all. It's developers concern.
Also UC has much more features and builtin contents than chrome. Maybe UC can provide better user experience to new internet users that think typing urls on phones to see news and videos weird. Not everyone likes minimalism.
At least Chinese markets (and possibly Indian and others as well)do not seem to have the disdain for feature loading American markets do.
Weibo is one of the most popular apps in the markwt (if not most) and it’s practically an operating system of its own. I suspect it would have gotten nowhere in US markets because people would have complained about it being not focused and having a bad UI.