Polling notification gets stuck spinning after network is disconnected

[bbhtt]

Checklist

• [X] I have used the search function to see if someone else has already submitted the same bug report.
• [X] I will describe the problem with as much detail as possible.

App version

6.305

Where did you get the app from?

Google Play

Android version

Android 7

Device model

A1-0301

Steps to reproduce

IMAP account set to manual polling, no push.

1. Open K9Mail while being connected to network
2. Pull to refresh the email list, see the "Checking new mail" spinner appears
3. Disconnect from network
4. See that the spinner continues to spin and the notification doesn't get dismissed. (I have to force stop at this point)

I suspect this has something to do with pfDNSFilter which runs as a local VPN and waits for the network to come back up.

Expected behavior

The notification should get dismissed immediately

Actual behavior

It doesn't get dismissed.

Logs

k9mail-logs.txt