What is this blue pulsating circle?

This is a screenshot of the circle I'm referring to. It was changing over time, sort of pulsating. The screenshot is of a portion of the screen showing my browser window. This blue circle stayed in front of any screen I switched to, until I switched to Photoshop. Then it disappears. That leads me to believe it's Adobe software doing it. I'm using a 16" M4 Macbook Pro. Searching the internet for explanations I see other Adobe products are implicated in this same issue.
What is the animated icon meant to represent? How can I prevent it in the future? I really don't know what I did to have triggered it. Hovering over it and clicking it did nothing. So it's a useless feature. Worse than that, it's an annoyance, since it encumberts other applications.
