I had this once on my old 27" iMAC (late 2015). A system restart fixed it. Never really did know what it wasFirst time I am seeing this. What is the tiny gray dot next to the LightRoom icon in my dock?
MacPro 2019
macOS Ventura
It‘s probably a stuck handoff icon. Do you have an iPhone, iPad or Apple Watch with handoff enabled? I usually have this with a tiny green blob, which ends up being the Messages app from my phone (opening the app there and then backing out of it on the phone usually removes the blob on macOS).
I'm still curious about the possible link to Handoff. Do you have an iPhone, iPad or Apple Watch with handoff enabled?I did as webbga suggested; rebooted. The dot disappeared.
That dot, the indicator for open applications, is below the app when the position of the Dock is the bottom edge of the screen.In my dock, the dot indicates that the app is active and running.
Quit the app; no dot. You can disable it in Desktop and Dock in system settings.