On Windows, right now, the Taskbar Icon is set to our C7 icon, but the Application Icon (which shows up in Explorer) is the default Godot icon.
Godot has a helpful guide to explain why this is and how to fix it: https://docs.godotengine.org/en/stable/tutorials/export/changing_application_icon_for_windows.html
(I am not sure whether a similar issue exists on Mac/Linux, but I don't see it listed as a dedicated topic in the Godot help system for those platforms)