I have created a circuit

and set the tunels.
I also created the package with pins.
However the circuit is not saved as .subcircuit , if I check the content of the file it has <circuit> tag inside, but it must have <subcircuit> tag as I can see it in the share/data directory.
How do I create a Subcircuit file ? I cant see any option like "New subcircuit" when I right-click the mouse.

and set the tunels.
I also created the package with pins.
However the circuit is not saved as .subcircuit , if I check the content of the file it has <circuit> tag inside, but it must have <subcircuit> tag as I can see it in the share/data directory.
How do I create a Subcircuit file ? I cant see any option like "New subcircuit" when I right-click the mouse.