Mail app in macOS 26 stuck on downloading messages

Mail app in MacOS 26 seems stuck saying it's "downloading messages." I have a few mail accounts, but sending emails from a separate account to each one lets the new email in. I've thought about the possibility it's re-downloading old mail after the OS update, but it's been a few weeks now.

When I reboot the app, the issue goes away, but returns if I wake the computer back up from a sleep. Example: I had 117 messages downloading when I started to ask this, by the time I finished checking things out and writing this question, it was up to 134 messages being downloaded. However, on restarting the app, it re-opened with only 4 messages being downloaded, and I could see it count down and then the "downloading messages" window disappeared when they were all downloaded.

Q: Any idea whether this is an account issue or a MacOS downloading issue, or a Mail App issue?

Q: If it's an account, is there a way to tell which account is causing the issue? The Activity window in Mail just shows that there are downloads going on (although the little progression bar does not move). All of the accounts are online with no indication of issues.

Jas

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