This message shows up in the middle of my work over and over again no matter which button I click?

Just hit the Update button and get the latest version of the add-on. Adobe must have released some patch for the newly-detected vulnerability.

I realize that. But the update gets stuck once I click the Update button and all I can see is a black box. I have no choice but terminate the process to close the box. Also, I keep seeing this message every two and three days after I update once before. Why there are so many updates? Is it possible that something is wrong with my browser settings?

I guess it depends on the network connection. Try restarting the update procedure again when there are no other workloads on the same machine.