Thunderbird Community Forum

For a few days I'm having trouble with Asana mails (notification mails informing me about replies, comments, etc).

Clicking on the mail to view it freezes Thunderbird for a good 5 seconds while one CPU core spins at 100%. This only happens with Asana mails (or at least I haven't found any other problematic senders).

I guess it's a problem with validation or parsing of the mail's HTML content. But I don't know how to debug this.

I can't pinpoint exactly when it started happening, but it was around the time I've switched to the [new snap release track](https://support.mozilla.org/en-US/kb/channel-choices-thunderbird-snap-and-flatpak#w_snap-channel-changes-in-2026). But since this happens with Snap and Flatpak I think the culprit may be the 153.0 update.

Things I've tried:

• Clearing cache and msf files.
• Troubleshooting mode with add-ons disabled.
• Reinstallation. Creating new profile + importing old data.
• Switching from Snap to Flatpak
• Switching Message Body display to Plan Text or Simple HTML.
• Disabling HW acceleration.
• Checking console for suspicious output.

Anything I can do to create handle the problem or collect information for a proper bug report?

I prefer to have the Contact Name only display in the TO: field of composed or outgoing emails. I already know their address is correct in my Address Book, why do I need to see it? Presently, the TO: field shows "Name <email address>", as shown in the first uploaded image.

I am a new user to Thunderbird and I have reviwed, and believe, set all the Settings correctly that I could find on the subject (see second uploaded image), but the results do not change.

What am I missing?

Thanks Matt T

Please excuse the length of this but it's necessary.

Began using Thunderbird (TB) in June, 2026 accessing email from wowway using POP3 (I know not imap, but old habits die hard). Changed password on wow in July and changed it in TB. Thereafter, and up until yesterday, TB was unable to logon to wow. However, the new PW allowed access to emails by browser logon to wow; old PW failed as it should. Frustrated with not being able to use TB with new PW: - deleted AppData/Roaming/Thunderbird folder (profiles and all) - recovered a backed up copy of TB folder from mid June when things were working and copied it to AppData/Roaming. Bingo, was able to get and send emails. Puzzled, looked at TB Saved Passwords and verified the old PW was being used. To verify this, I sent an email to myself, pressed F5 to get mail and it was in the inbox, and also on wow server.. BOTTOM LINE: There is no question that TB is using an old, changed wow PW. And if PW in TB is changed to new PW, access to wow fails. How can this be? Help please.

There was an earlier Case with the exact same name as what I named this case which was archived back in 2025. I have been living with this same problem since last year also. In the previous case there was reference to "downgrading" to an earlier version of TB, but there have been a bunch of updates since then so I doubt that would fix my problem because that earlier version is now over a year old.

I have one Gmail folder that correctly has one folder label "Junk." However, I have 4 folders that are AT&T related (2 from the domain "sbcglobal.net" and 2 from the "att.net.") For some reason when I set these folders up years ago they started out as labeled "Spam" instead of "Junk." Of those 4 folders 2 of them have the duplicated "Spam" folders, one from each domain."

When I go to Folder Properties I see "imap://XXXXX%40sbcglobal.net@imap.mail.att.net/Junk" on one of these Spam folders and "imap://XXXXX%40sbcglobal.net@imap.mail.att.net/Bulk" in the other. And the same "Bulk" vs "Junk" issue is in the other domain as well. All are named "Spam."

Can I simply delete one of these folders that are named "Spam" in each domain? Does it matter whether I delete the one ending in "Junk" or the one ending in "Bulk?"

Thanks.

just got Thunderbird, i added my outlook email then got to the "connect your email setting" then i clicked continue cause i wanted to use imap and got a "Authentication error". I got Thunderbird on a different device and used my gmail on that device and it worked fine. Only get the error when i try to use my outlook email and i don't know what to do.

My eyesight5 is pretty bad. I'm trying to make the display fonts quite large (32), but nothing seems to be working. The settings allows me to select a font and set the size from a pull down list, but nothing changes. Presentation and functional operation should be isolated from each other as possible.

Hi, It worked flawlessly in the previous version. In version 153.0.2esr (64-bit), I can't drag and drop messages to a folder (e.g., Desktop). Does anyone have any ideas on how to fix this?

I went to View and tool bars... Composition was already enabled. Alt and F10 did not reveal "Send." I tried to use the "Customize" menu and it did not include "Send." I do appreciate your help, even if everything suggested so far has not worked. My fear is that I may have to delete my Thunderbird in its entirety and re-install. If I do this, is there a way for me to save my address book? Is there still a way for me to get my Send back.

I may have to just settle using <Ctl> Enter on my keyboard. Bill

The SEND button has vanished in Thunderbird. I don't recall changing anything or performing any updates, though my memory is getting to be unreliable.. In addition, the LINK button has vanished as well. I imagine I did or am doing something stupid and it's an easy fix, but what that might be totally escapes me..

Thunderbird stopped retrieving mail from one of my accounts, does not give an error message, just says no new emails, Outlook and other devices are continuing to retrieve from this account with no issue. So the issue is with Thunderbird. Is there a text or phone number I can use with tech support to clear this issue? I checked with AI Bots to resolve this and it seems quite involved.

Thank you. Rafael

1) How do I get the emails Thunderbird marks as spam to be moved to the Spam folder without me doing anything. I have thousands of emails now most marked as spam but I have to go in and move them one by freaking one!

2) Also you freaking filter system doesn't work worth a crap! I have created filters for instance: for any emails that have @cypress.com in the From part of the message to be moved to a folder under my inbox named Cypress. I have run it many times and actually none of the filters I've created work? They are very simple to understand and I am doing them correctly as far as I can tell but they don't work. I have created at least a dozen filters and the only emails moved are ones I moved manually myself.

And this training crap you have I don't know what you think it should take a computer to learn to move something to a folder. It's not like a child that has to be taught how to spell. You tell it if it has this in whichever field you've selected then it should move it. Not have to be taught? Not a bright idea in my opinion. It's why AI isn't very smart at least what they release to general users. Anyway I digress.

If you can help me with the above issues in the above paragraphs 1 & 3 I would greatly appreciate it.

I have used Thunderbird on a MacBook Pro Max M4 for a while now. It worked fine until starting last Monday. Ever since then, I have to go to 1&1/IONOS e-mail on the web to send e-mails or use my iPhone and blind copy myself. It’s a pain going back and forth.

1&1/IONOS tech support helped me make sure all settings for the outgoing server (smtp) were and are correct. Tests on both incoming and outgoing ports are successful in the Thunderbird settings, so I don't understand why my e-mails are not sending. I have no problem receiving e-mails on Thunderbird. This problem on outgoing e-mails applies to both text-only e-mails and e-mails with attachments. Screenshots are attached.

There is 17.9GB worth of data. Do I perhaps need to delete some of it? I archive old e-mails offline once a year, generally in January for the previous calendar year.

Thanks, Tim

Hi using 153esr and Win11

I have my emails on an encrypted drive. Until now if I closed Thunderbird I would have to enter my Master/Primary password before and emails would show, i.e they were protected from casual view.

Now if I type [cancel] at the request for a password, twice in a row than all my emails are visible.

I though it may be this new thing where the [close] icon functions differently, but even if I close via the menu File > Exit it seems Thunderbird still has access to my emails without authorisation.

Any ideas would be useful

Thanks

Recently updated to ESR Meadow.

Now when I try to save attachment from an email by dragging and dropping to desktop, Windows pops up "Error Moving File or Folder - Unspecified error" and the operation fails.

And when I try to save attachment from an email by right click > open > Save dialog, the save filename is always "nsmail" but with the original file extension. E.g. a jpg attachment would come up as "nsmail.jpg", and a txt file attachment would come up as nsmail.txt. It does then save it, but why lose the filename?

It used to preserve the attachment filename, I'm sure! And drag and drop to desktop was such a convenient feature!

I have tried in Troubleshoot mode and behaviour is the same. I have tried in Windows Safe mode and behaviour for Save is the same; but drag and drop is completely disabled there (when I drag it, it shows a circle with line through icon).

Is it just me?

I use a number of add-ons to help me out. Unfortunately, the following add-ons aren't working right now: Quicktext, Send Later, TbSync (where and how do I integrate it into Thunderbird?). When sending an email, I have to go through “File” > “Send”—there’s no button for it. The VBA call to send a generated email truncates the string, so the attachment isn’t included.

I’m sure some add-ons will be updated. But this is hitting me hard right now.