Unintuitive back button after saving server settings

Checklist

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

App version

6.713

Where did you get the app from?

F-Droid

Android version

Android 14, GrapheneOS

Device model

No response

Steps to reproduce

1. Go to settings
2. Choose an account
3. Tap 'Fetching mail'
4. Tap 'Incoming server'
5. Change incoming server
6. Tap 'Next'
7. K-9 mail will now show "Incoming servers are valid 🎉" with a back button
8. Pressing this back button will bring you back to the incoming server settings page, showing the new server. However, if you re-open this setting page, you will see the previous values again. Turns out the settings are not actually saved.

Expected behavior

I would expect to see some sort of indicator that the settings are still being saved, and that "Incoming servers are valid" is not the final success page.

Actual behavior

After seeing "Incoming servers are valid", you need to wait several seconds before it changes to "Saving server settings successful". There is no indication that I needed to wait for this page, so I thought pressing the "back" button was the only option.

Logs

No response