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Hello Folks,

We are a team of around 15 users who have been using Mozilla Thunderbird with Google IMAP for the last few years. Until recently, Thunderbird has been working reliably without any major issues.

However, for approximately the last one week, we have been facing a serious performance issue with incoming emails. Around 12 out of 15 users are experiencing the same problem.

The main issues we are facing are:

Newly received emails take a very long time to download. After clicking on a newly received email, it takes a considerable amount of time to open and display the content. Emails appear to be downloading extremely slowly, even though our internet connection is a 100 Mbps ILL (Internet Leased Line). The issue is affecting multiple users simultaneously, so it does not appear to be limited to a particular user's Thunderbird profile or PC. We have already tried Repair Folder / Repair Inbox, but the issue persists. We are using Google's IMAP servers for our email accounts.

We are currently using Mozilla Thunderbird 153.0.3 (64-bit) – Meadow Badge.

Could this be a known issue or bug in the latest Thunderbird 153.0.3 update, particularly with Google IMAP?

We would appreciate any guidance from the Thunderbird community/support team on how to troubleshoot and resolve this issue. If there are any recommended settings, logs, diagnostics, or Thunderbird configuration changes that we should check, please let us know.

Since this issue is affecting 12 out of 15 users, it is becoming a significant operational problem for our team.

Any help or suggestions would be highly appreciated.

Thank you.

Hello Folks, We are a team of 15ppl using thunderbird from last few year and it work flolessly in these years but from last 1week i have been facing a serious issue of : INCOMING EMAILS TAKING A LOT OF TIME TO OPEN AND READ, fresh email when received and after clicking it takes a lot of time of open, having a 100mpbs ILL speed, out of 15 / 12 ppl are facing same issue, even after repairing the inbox the issue remains same, mails are getting downloaded very slowly...we are using google imap server for the same, need help to resolve the same...is it the bug in the latest update 153.0.3 (64-bit) Meadow badge

My Firefox created a new profile and reset everything. I was able to go back and locate my bookmarks and restore them, but my menu bar is reset, my history and saved passwords etc are all gone.

Firefox version: 153.0.4 / Windows 11 25H2 26200.9168

Attached are images showing the performance settings and the active extensions in case any of them proves to be responsible for the problem.

Yesterday I noticed a horizontal screen tear when scrolling down through sites like X(Twitter), YouTube, GMail, Reddit etc. I immediately checked my performance options and they were deselected. I activated them again, but this did not solve the problem, I also tried to active some layers in about:config but those were already activated. Checked Nvidia settings too, vsync is on, Edge is not affected, Chrome is not affected, even installed Waterfox to see if only Firefox-based browsers are affected, but that one was OK too.

Last resort was to refresh the Firefox installation from the uninstall utility. After the refresh and all settings/extensions got auto-reinstalled, the screen tear got fixed. I left the PC running over night and when I accessed Firefox again this morning, the screen tear problem was back. However, now, the performance options are disabled, and if I try to enable them and restart Firefox, the options get disabled again.

Would really appreciate it if anyone could provide a solution that does not involve refreshing Firefox daily.

I have followed the instructions that several people give to transfer my existing Thunderbird installation to a new computer where I have just installed Thunderbird. That is I copied the Thunderbird folder and put it in the Roaming folded found in %appdata%. Both computers are on Windows 11. When I open the new Thunderbird, it does not recognise it. Furthermore, in Help>Troubleshooting information>Profile folder when I click to open the folder, it looks for a folder that is not in my previous Thunderbird installation: qr19mupe.default-release instead of the one that came with my imported Thunderbird folder. Has this happened to anybody and found the solution? Can anybody help please?

メールソフトをアウトルックからサンダーバードへ移行したく、サンダーバードのアプリはダウンロードしましたが、 サインインに失敗なのか？認証できなく困っています。受信サーバーはIMAPですが、サンダーバード ではPOP3とでてきたので、手動でIMAPにかえてもみましたが、とにかく認証しないのです。 どうしたらよいか教えていただきたいです。

I have a new PC. I have added five email accounts, three different hosts, with some difficulty. Thunderbird finds the details for others but then refuses with the message Authentication error. Unable to log in at server. Probably wrong configuration, username or password.

I added Thunderbird by copying from my old PC. The hosts for those not yet added are the same as those added.

Bonjour, Je vous promets que je vous fais un don dès que vous aurez mis fin à votre publicité mensongère à propos des Dossier récents : ils ne sont jamais triés par ordre alphabétique, quelque soit le paramétrage demandé.

Please provide a clear, step-by-step troubleshooting solution specifically for Firefox for Android. Explain the possible causes of choppy YouTube playback and show me which Firefox settings to check or change, including hardware acceleration, extensions, video quality, cache, and performance settings. Please explain what to do at each step and how to test whether the problem has been fixed.

the password logins are confusing.disturbing and stifling my project,i need to log in to Carprog Online but your password page wont allow me therefore delaying my time in

I can't download some pdfs, notably my bank statements. I CAN download some pdfs. Eg, I can download my car manual (although it's a process of downloading it to my Google Drive). However, trying to download my bank statements, Firefox gives me no options at all, and, indeed, I get an error message. Yet I CAN download my bank statements using Google Chrome! I've carefully checked all my Firefox settings, but nothing seems to address this problem. I've spoken to my bank, and they don't know why I can't download them either. When I try to download the statements, I get a screen saying it can't give me a 'Preview' (see attached screenshot), but there's a 'Download button. When I click that I get a white screen with the 'error' message:

"No API key found in request. request_id: d52e0732a3d10a75b1ec58534845c15c"

(2nd attached screenshot.)

I have asked about this before on this forum, but to no avail.

YouTube videos are playing choppily in Firefox. The video frequently stutters/freezes or does not play smoothly, even when the same videos work normally in another browser. I have restarted Firefox and my device, but the problem continues. I would like help identifying whether the cause is hardware acceleration, Firefox extensions, graphics drivers, or another Firefox setting, and I would appreciate step-by-step troubleshooting instructions.

Please provide clear, step-by-step troubleshooting instructions to identify the cause of the problem and explain how to fix it. If possible, include the Firefox settings I should check and any tests I can perform to determine whether extensions, hardware acceleration, graphics drivers, or network settings are responsible.

Been using Thunderbird for a number of years but recently the SSD on my laptop became corrupted and I had to buy a new one and install TB and restore my profiles from a backup.

I have two accounts and switch between them with Profile Manager.

The new laptop is an ASUS Vivobook with Win 11 Home and although TB runs ok the first time, if I close the current session and try to open the other account, nothing happens when I click on TB icon on the taskbar. IF I wait for around 5 minutes then it will run

Checked in Task Manager and cant see any instances of TB running, so any thoughts on what's wrong. Does not matter which order I open the accounts.

My Mac last night lost thunderbird (and numerous others things) and it's setting itself up again. I get an error that smpt already exists and I can't go any further! What's going on? Using Comcast Mail.

On my iphone google assumes everyone is in the US, even if you add UK to every search. Is there a way to make it search for local answers ? on desktop I have an extension to change it from .com to .co.uk is there anything similar on IOS

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