Saving one-line block descriptions in Xcos

Bug Description

XCos does not seem to save one-line block descriptions.

Steps to reproduce

I create a superblock:

I rename the inport and output ports to something more custom using the one-line block description field:

The names show up on the icon of the superblock:

However, when I save, close and reopen the file, the custom port names are missing.

What is the expected correct behavior?

I would like to see the port names reflect on the superblock icon after reopening a saved file.