Is there any special setting for DeltaChat in firewalls?

Delta Chat version

Expected behavior

Actual behavior

Steps to reproduce the problem

Screen snapshots

Debug logs

Logs
<!--
If applicable, debug logs can be copied from within the Delta Chat app: 

Open the _Settings_ menu -> _About_ -> _version number|Info_.

Alternatively from the Android system log:

` adb logcat -v time -s DeltaChat `

This log contains private data (e.g. mail address, provider information) which shall be removed or anonymised prior to posting.
-->


Which ports should be opened for deltachat in firewall

the IMAP & SMTP ports of your email provider?