Apps opened from the GUI inherit the port, block next launch

[efermi]

Using Linux, GUI version of the program, no UPnP:

1. Open qb. netstat:

tcp        0      0 127.0.0.1:6881          0.0.0.0:*               LISTEN      3410905/qbittorrent 

2. On an existing torrent: Open containing folder.
3. Close qb but keep the launched app open. netstat:

tcp        0      0 127.0.0.1:6881          0.0.0.0:*               LISTEN      3411040/dolphin     

4. Open qb again: Address already in use

Could this be avoided in some way? Is there another way to launch external programs without them inheriting open ports?