I find it impossible to just use one computer operating system where I am. Windows will not often be able to access Yahoo but Linux always will. For Wechat Windows does some things better and Linux is better at others. I try to use Widows rarely as it's heavy on the CPU and will age your computer before its time. Wechat will speed up your fan on Windows.

Actually before I left Blighty I managed to get a friend to send an American I had worked with years ago a degree. I learned after getting to China he had secured a job in Shanghai with the degree. I even know the date when he boarded his aeroplane from USA. After that communication ceased so I don't know how he faired with his new teaching job. I assume he can't get Yahoo in Shanghai. Pity I can't inform him to advise him to use Linux.

Sorry, I can't help you. I know little about computing. I know Google is blocked in some parts of China. Yahoo too? It works here, but I seldom use it. I prefer Bing.