On Windows:
- Check out
ITaskbarList3::SetProgressState
Example:
On macOS:
- It seems to be a matter of adding a custom view to the dock icon.
- Maybe a hint: https://stackoverflow.com/a/10316872
Example:
On Linux:
It’s pretty complicated for nothing, as expected with the total lack of consistency on this OS and insane set of variations.
- Possible hint here using dbus and some wacky file manipulation: https://stackoverflow.com/a/43919667
On Android I don’t think this is possible.
I also have no iOS devices to know if that’s a feature on there.