Thunderbird uses limed message fatching and in the case of some servers like google utilizes push notifications as well.

Push notifications have sever limitations on the number of folders they work with and can only be sort of relied on for mail in the inbox.

Times mail fetch will occur in the time frame in your account settings. But not all mail folders are polled for mail. Specifically the trash/deleted and junk/spam folders are not polled for new mail unless you select them. ( right clicking the folder and selection properties allows for a folder to be included in the fetch if it is not.) Having said that various things can see a folder deselected, so check they are included in the folders to be polled for new mail.

I have seen new mail slowed or dropped if it is subject to mail scanners from antivirus programs. So I personally do not recommend email scanning, nor do I use it myself.

I'm only talking about new messages in the INBOX. I tried what you suggested anyways: 1. I disabled scanning of email and browser activity. 2. I added all non-INBOX folders to the scan.

No change. Just this morning (June 20, 11:00AM), I have received at least 15 email messages dated and timestamped yesterday (June 19, before 1:00PM).

To reiterate, I never had this problem on any PC with the same email accounts and the same network settings. Until Thunderbird upgraded to the latest version, I had ZERO problems on this PC. To blame any other source for the problem is just unfathomable. The only change is the version of Thunderbird, therefore, the only possible source of the problem is, you guessed it - Thunderbird.

Where can I file an actual bug report for this problem?

before you file a bug report, I suggest you create a log of the process. Because I find in unfathomable that an IMAP server would not offer any new mail to be downloaded.

You will need to use GEKO logging of IMAP in V115. See https://wiki.mozilla.org/MailNews:Logging

A bug can be reported here https://bugzilla.mozilla.org/home but should be supported with evidence of what is happening. Developers need to reproduce things to test their fix. So determining the cause is often more important than the fix.

I also suggest you examine the headers of the messages. The date header is added at the time of submission to the SMTP server and really has nothing to do with the delivery time.

Also make sure accounts are set to get new messages no more frequently than 15 minutes. You might have had this set to things like 2 minutes in the past, but 15 minutes eliminates issues with servers still connected. It is a fairly standard diagnostic.

I have no idea what you mean when you say you added all non inbox folders to the scan> Personally I would just remove the antivirus. Windows has one that is perfectly adequate for most things and it needs to be eliminated as a cause.

Polling is every 20 minutes. The only scanner is whatever is built into Windows 11 Pro 64-bit. You suggested adding folders other than the INBOX by checking the box "When getting messages for this account, always check this folder" under Properties for each sub-folder, which I did. I deleted the account from TB and recreated it using TB default settings for gmail. The problem persists. Below is the header of a message that arrived in my Gmail INVOX on time (I used the godawful Gmail website to read my messages for a few days), but was NOT retrieved by TB until late the next day. It is a polling problem, not a delivery problem. I have not coded since I went blind in 2001, and the document you referenced is a confusing mishmash of variables that don't help me define a proper debugging protocol. The sample batch file gets me started, but which additional bariables need to be set to capture what a developer might need? Also, I've found dozens of references to this problem in prior versions going back at least 5 years (with both comcast and Google), with no resolution for any of them either.

Delivered-To:answergrape.68@gmail.com Received:by 2002:a05:6022:5a:b0:57:ca62:e522 with SMTP id 26csp3033877lar; Wed, 19 Jun 2024 07:01:12 -0700 (PDT) X-Google-Smtp-Source:AGHT+IEh8t15GD7Bn+yhQn3uvLA11W7kIf1l+zfhzDV545z0zcOO7TpOfnTK6VAgi15pRDRfN/ev X-Received:by 2002:a17:90a:ec08:b0:2c2:d66d:1b8c with SMTP id 98e67ed59e1d1-2c7b3bdef33mr3856889a91.20.1718805671606; Wed, 19 Jun 2024 07:01:11 -0700 (PDT) ARC-Seal:i=1; a=rsa-sha256; t=1718805671; cv=none; d=google.com; s=arc-20160816; b=ptkwQx3rdJP171fwapiLy17AgnsgtqsnXZTvay8IaaePEdAYSNIt2m2+Rg+PppARcc BdQDRzTRv7A9vYW9LCcZSMZVmot+i2OdmWtg4cHjtUSAlD0xuDcQ62iqOUuse387f0qs LbxoIl+5nlIMd3U6q68kGGQjzjhhFwKPEn0zuQ2KAjwAnD2SBQgSnrmYfjZBQYZJI52Z YtMmmRJjaYkyn3/tMraFBKQ/DPFCIRpglGujSEj9roi8fqXuXpoiXTBCzoJBVxp0jrDK VLX3Ob8RlrXEuR7zcdbasuwvSuUjO7T2b6zUJJOWlwoZU+IcO7Ei0g5cHR1BwmXxXmyT meFQ== ARC-Message-Signature:i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=feedback-id:from:subject:list-unsubscribe-post:reply-to :list-unsubscribe:mime-version:date:message-id:to:dkim-signature; bh=5T75iEvvJ7Yv+DjphJfqsEKp6cEmpk54aKlLaYlk6Go=; fh=48D4nPtJc29+hMYL7z/0ZSEMngnmCVJem6wbQtLj0pY=; b=hS+mS99h90SAaEtrb1f1OvsEV+VURhEsF1S9yzdQHpT2IxvXJeSGKppN1lLuyZVAnK p1fULPc/ehxy+6RteW2fbLiNudcEpLZbEngfCmR5HCZqwTdzm/CdpL7W26EPTjkHrvlV G4VZPjMgX15kyX3NJ9/zHjBIAMG80b9+sWnfYrtNMmIpE2nlVPqxZHCSDhqcOfSJe9Lm CWRXC5nGGi+sKCO/xRtOl0MRr5sYMocNaLqgPy5SAUzhYVFHHPx12YvABDtqgjdULVzU njr19s+kR1r4YFpDyDoe/+Ylqzn1hvGK3cwa5irkT/tBGsgHhkmYT270csR/a7G5t3wY NBMw==; dara=google.com ARC-Authentication-Results:i=1; mx.google.com; dkim=pass header.i=@email.paradigmpressgroup.com header.s=scph0722 header.b="oAM/oQu3"; spf=pass (google.com: domain of msprvs1=19900prvkuces=bounces-280172-1015@bounce.email.paradigmpressgroup.com designates 156.70.2.220 as permitted sender) smtp.mailfrom="msprvs1=19900prvKUCes=bounces-280172-1015@bounce.email.paradigmpressgroup.com"; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=paradigmpressgroup.com Return-Path:<msprvs1=19900prvKUCes=bounces-280172-1015@bounce.email.paradigmpressgroup.com> Received:from mta-70-2-220.sparkpostmail.com (mta-70-2-220.sparkpostmail.com. [156.70.2.220]) by mx.google.com with ESMTPS id 98e67ed59e1d1-2c500226170si8269399a91.129.2024.06.19.07.01.11 for <answergrape.68@gmail.com> (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 19 Jun 2024 07:01:11 -0700 (PDT) Received-SPF:pass (google.com: domain of msprvs1=19900prvkuces=bounces-280172-1015@bounce.email.paradigmpressgroup.com designates 156.70.2.220 as permitted sender) client-ip=156.70.2.220; Authentication-Results:mx.google.com; dkim=pass header.i=@email.paradigmpressgroup.com header.s=scph0722 header.b="oAM/oQu3"; spf=pass (google.com: domain of msprvs1=19900prvkuces=bounces-280172-1015@bounce.email.paradigmpressgroup.com designates 156.70.2.220 as permitted sender) smtp.mailfrom="msprvs1=19900prvKUCes=bounces-280172-1015@bounce.email.paradigmpressgroup.com"; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=paradigmpressgroup.com X-MSFBL:QcP+LvZwtLKbsEpY+UrShqchBqMnejSLiLBSA3Y5XRc=|eyJjdXN0b21lcl9pZCI 6IjI4MDE3MiIsInIiOiJhbnN3ZXJncmFwZS42OEBnbWFpbC5jb20iLCJzdWJhY2N vdW50X2lkIjoiMTAxNSIsInRlbmFudF9pZCI6InNwYyIsIm1lc3NhZ2VfaWQiOiI 2NjcxYTBlNDcyNjY3MzU0MDViZiJ9 DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=email.paradigmpressgroup.com; s=scph0722; t=1718805664; i=@email.paradigmpressgroup.com; bh=5T75iEvvJ7Yv+DjphJfqsEKp6cEmpk54aKlLaYlk6Go=; h=To:Message-ID:Date:Content-Type:List-Unsubscribe: List-Unsubscribe-Post:Subject:From:From:To:Cc:Subject; b=oAM/oQu3uTryW0H408mPL5jvp/ejaKH06t5yWTgXG3qnzMNe++Fk1IyHulNcu98hK yH6vRh1kYiB9Dh4Y1db91VoIhC2ox2f/aYqJygRR78pmrggU/zqmMveA0Rmngtjwa1 pApHEj5XVRwZ7bTmG2NEyNoeLymBxPpj7D3Q1gSA= Content-Type:multipart/alternative; boundary="_----wlkWSmm74jlJ4/mwLjIPCg===_2A/58-29641-0A4E2766" MIME-Version:1.0 X-Campaign-ID:10200678 List-Unsubscribe:<https://links.paradigmpressgroup.com/e/encryptedConfirmUnsubscribe?_r=401af7ee249b46f598fb2a91ce659915&_s=799aa9eb3bce49d1a0ae564796bc2174&_t=pFrloTtF05Ppv7nDWNgmrYpPyy7iuhwNc0dSr9WiwLTq1uGosM5rYl5qpch-lGVGHJ1XkXeMCPkKnatvdrU-dHEl1egHNlYiPq2GK0dt7lwTZ0kez64J4Oq7-eV9f8iwYybDShDTKnlQCBEm0qJ4OTqhAfsRF9SR8w0WqQGGZNo%3D>,<mailto:unsubscribe+10200678+13458127@unsubscribe.iterable.com> X-Message-ID:799aa9eb3bce49d1a0ae564796bc2174 X-Feedback-ID:13458127:10200678:67972:iterable List-Unsubscribe-Post:List-Unsubscribe=One-Click Feedback-ID:13458127:10200678:67972:iterable

Additionally, forcing a "Get New Messages" or restarting TB do not make the messages I can see through the native Gmail interface (or Comcast's for that matter) appear any faster. Note that MOST messages, even from the same sender, appear when they are received by the email host (Gmail or Comcast). Meanwhile, others delivered to the host at or near the same time do not get retrieved by TB. I hope this clarifies things.