Thanks for looking into it. That does sound strange. My mobile internet connection is flakey at times; but unlike a regularly failed request, there isn't any e

Thanks for looking into it. That does sound strange. My mobile internet connection is flakey at times; but unlike a regularly failed request, there isn't any evidence of failure for voting (BTW I noted that SO does give an alert if this happens for their votes.) I also tried it again and found sometimes it fails even on a "fresh" page (and as you've explained, that shouldn't make any difference anyway). It may have just been a coincidence when refreshing worked. I'm having a lot of network problems recently, so that may be it. But it's also definitely happened in the past, when I wasn't having any such problems. "The network is unreliable" - this would also explain why several other people have experienced this behaviour, that looks like expired links. Heh, probably the HN maintainers have great network connectivity, and so you mightn't ever see it yourself.