system-taskbar

Use this package to display a taskbar icon "badge" overlay, a
progress bar report overlay, or alert the user that an Emacs session
needs attention, often by flashing or bouncing the Emacs application
icon.

Note: The term taskbar is inclusive of dock or launcher or some other
terminology as may be used for your system.

On GNU/Linux, the visible effects will appear on the destinations
determined by your shell extension, most often the application
launcher or dock panel, or the top panel.  Effects are global for an
Emacs instance.

On macOS/GNUstep, the effects will appear on the Dock and in the App
Switcher.  Effects are global for an Emacs instance.

On MS-Windows, the effects appear on the taskbar.  Effects are
associated with the frame from which they are initiated.