Diễn đàn hỗ trợ Firefox

I have a 100% repro rate of Firefox redirecting linkedin.com to linkedin.cn. Unfortunately there's another problem beyond the unwanted redirection: linkedin.cn no longer exits, it has been dead for years, I literally cannot reach LinkedIn at all. It was working fine a week or two ago. How do I prevent Firefox from redirecting behind my back? I see the status message (is that what it's called) in the lower left corner "Performing TLS handshake to www.linkedin.cn" and of course it only times out. I just verified with "Web" (different browser), it connects just fine, which suggests that it's a Firefox issue, not a system wide one.

I don't know what's happened but Firefox makes sites think I'm a bot. I keep being asked to verify I'm human, I tick the box, it spins and fails. I tick again, it fails. I have tried these sites on other browsers and it works so it's something going wrong in my Firefox. It happened after I loaded Protect My Choices and now even though I've disabled it, it doesn't work. I've amended to Standard in Privacy settings but that doesn't work either.