Firewall port to allow for push notifications

[bbiw]

Hello all,

i've installed an app that warns me e.g. in the case of fire. It was removed from the OpenStore, but it's source code can be found here: https://github.com/S60W79/warnapp-deutschland or https://gitlab.com/S60W79/warnapp-deutschland.

The problem is i've activated ufw and because of that i don't receive the push notifications.

Does anyone know which port to open for this or a way to find out which port is used or which firewall rule to set?

Thanks all!