`Local folder size` setting arbitrary displays messages in `sent messages` folder

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

K-9 Mail

App version

8.9b5

Where did you get the app from?

Google Play

Android version

15

Device model

Pixel 7a

Steps to reproduce

1. Add email account (use standard settings); in this case it was a Strato account
2. Go to Sent Items folder
3. You'll see there is a gap from the emails sent from this phone recently (like today); my last email for that bunch was in 2021

Workaround:

When I got to Settings → <select_account> → Fetching mail → Local folder size and select all messages (instead of 100 messages as it was selected before)
I get now all messages.

Related forum entry: https://forum.k9mail.app/t/missing-emails-in-sent-items/10649

Expected behavior

I am expecting the last 100 messages to be displayed.

Actual behavior

What is not expected that with the 100 messages setting I don’t get the last 100 but some (random?) 100 message.

---

Could be some regression since this behaviour is new (maybe a few weeks old) and the account settings did not change.

Logs

No response

No source file or test is named. First reproduce the issue with a standard account in Sent Items using the 100-message Local folder size setting, compare it with All messages, and trace the account's folder synchronization and message-limit entry points. Done means the setting consistently displays the latest 100 messages rather than an arbitrary set.