xenialpup 7.5-Calibre web server-Firewall

[soniabu]

SOLVED
Open Firewall setup, then extras function activated after checking "change it to open port"
A new window opens up that I filled in this way for my problem:
8080,TCP,UDP
that's all.
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Hi, everybody.
I am trying to distribute my library Calibre 3.34 - through the server of Calibre - server that wants the opening of port 8080. I use the Firewall in the generic version as it was in the installation phase of xenialpup.
I don't know how to open this blessed 8080 in the Firewall.
If I turn off the Firewall everything works because I can see my library from other
pc in the LAN; as soon as I re-activate it nothing more I see.
If anyone can show me a way to solve the problem, I'll be grateful.
sonia