I've had that happen from time to time for years. It happens a dozen times or so and then it works.
The old server used to go through periods where it would be slow for no discernible reason. I was never able to track down why, but my guess is that over the years the software updates became less and less compatible with the underlying OS and with each other. One thing that helped was restarting Apache once per hour. If anyone ever noticed that the website would be unavailable for a few seconds at 4 minutes after every hour, that's why.
Anyway, when the old server was being slow then Ajax requests would suffer a timeout and the request would be canceled, meaning that your "cheer" or your "acknowledge message" request would be ignored.
This shouldn't happen with the new server because it is in the cloud, meaning that we don't actually have a physical server. We're actually just running on a virtual machine that can run on any physical server of the right type (there are increasingly expensive tiers of speed and capability). I'm hopeful that software updates should be less of a cause of problems, but we'll see.
Yes, that's the one. Ajax is what allows just part of a webpage to be updated. A request to the server is made for information, and that information is used to change the webpage, for example by adding a "cheer" image. The webpage that you see in your browser has an internal representation, and by making changes to that internal representation you can change just portions of the webpage, instead of redrawing the entire webpage.
Sorry I overlooked these. Both look like well thought out topics.
Chance as a real force is a myth. It has no basis in reality and no place in scientific inquiry. For science and philosophy to continue to advance in knowledge, chance must be demythologized once and for all. ~RC Sproul "A lie can travel half way around the world while the truth is putting on its shoes." ~Mark Twain " ~"If that's not sufficient for you go soak your head."~Faith
You can "get answers" by watching the ducks. That doesn't mean the answers are coming from them.~Ringo
Subjectivism may very well undermine Christianity. In the same way that "allowing people to choose what they want to be when they grow up" undermines communism.~Stile