Email List Columns Changing Widths on Thunderbird re-Opening

I'm running Thunderbird 140.5.0esr (32-bit) on Windows 10 Pro Build 19045. After the last few updates the columns in the email listings are changing widths from what I'v… (funda kabanzi)

I'm running Thunderbird 140.5.0esr (32-bit) on Windows 10 Pro Build 19045. After the last few updates the columns in the email listings are changing widths from what I've set them, this seems to happen after I close then reopen Thunderbird; which I'm having to do more often these days to resolve weird calendar malfunctions. For instance, the data column would appear so narrow that only the month/day show with "..." at the end, when I know I've looked at this yesterday with the full view of the date and time showing. I've reviewed my options and I've set them individually, set them globally and it makes no difference. Of course I've rebooted, etc. I have over a hundred local folders and they all change differently, of course some look the same but others don't. Most have the same column headings selected but it doesn't seem to matter. Some have the "Correspondents" column selected but many don't.

This is very irritating and I'd like to know why Thunderbird is doing this, and more importantly, how can I prevent this behavior in the future. Thanks,

Open 24 126

Thunderbird hangs my computer/machine periodically, rarely

Thunderbird causes my machine to 'hang' from time to time, 1. often for up to a second and usually a number of times in quick succession on each ocasion. Sometimes this … (funda kabanzi)

Thunderbird causes my machine to 'hang' from time to time,

1. often for up to a second and usually a number of times in quick succession on each ocasion. Sometimes this happens frequently - say every 5 or 10 minutes - sometimes only after an hour or more since the past occurrance.

2. My machine hangs completely - nothing will work, mouse, keyboard, sound, other apps etc. If I happen to be typing (into any app - including Thunderbird - when this happens, input ceases, the cursor freezes and - if the problem persists for a second or two, Windows reports "[app] is not responding"

3. I cannot be certain, but I believe the problem occurs whilst messages are being retrieved.

This is a very serious problem as it means that I can never leave TB running as the problems it causes are not acceptable.

4. This means I cannot deal with incoming messages without periodically re-starting TB - which is an utter PIA.

I am running Win 11 Professional on a 2-year old machine with 64 Gb of memory. I have run TB in Troubleshoot mode, I have confirmed that the problem occurs regardless or whatever other apps are running (or none) and I have proven conclusively that no other app causes any kind of similar problem.

Looking forward yto hearing if others have had the same issue and what can be done about it.

Open 16 90

I cannot access the Chewy.com website on Firefox.

I can access Chewy with Safari, but not with Firefox. So the problem is not with my Mac settings and the problem is not with Chewy, the problem is with Firefox. Please … (funda kabanzi)

I can access Chewy with Safari, but not with Firefox. So the problem is not with my Mac settings and the problem is not with Chewy, the problem is with Firefox. Please address and fix it.

Open 15 1

New update Version 140.10.2esr | Released May 8, 2026. Today I cannot send email using Thunderbird.

Version 140.10.2esr | Released May 8, 2026 I get this message every time: Sending of the message failed. The message could not be sent because connecting to Outgoing serv… (funda kabanzi)

Version 140.10.2esr | Released May 8, 2026 I get this message every time: Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) mail.twc.com failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again.

Thank you, George Correia

Open 10 1

how to turn OFF the message preview when I single-click on message?

RE: How to turn OFF message preview when I single-click on message? When in TB message list, and selecting a message for an operation by making a single-click on the mess… (funda kabanzi)

RE: How to turn OFF message preview when I single-click on message?

When in TB message list, and selecting a message for an operation by making a single-click on the message, the selected message opens. When using CNTL key to select several messages together for an operation, each of the messages opens an individual preview pane. I have searched TB's knowledgebase, but apparently no other users have this problem.

Open 10 27

Lost my email and don't have incoming

Okay, so how to be simple. I kept getting a pop-up from Comcast about a latest promotion and it wouldn't go away. I spoke to Comcast about their ridiculous pop-up promoti… (funda kabanzi)

Okay, so how to be simple. I kept getting a pop-up from Comcast about a latest promotion and it wouldn't go away. I spoke to Comcast about their ridiculous pop-up promotion, it was coming through my Thunderbird email client. That may be taken care of. But in the meantime I tried to delete my main Thunderbird account, I must have done so and now I can't get it back! I've tried everything! I was using an IMAP account, and for my incoming I had imap.comcast.net. For my outgoing I had stmp.comcast.net and the ports were 993 and 587 I believe. Please don't quote me on this. So when I try to create a new email account using the same information I keep getting an "Authorization Error" each and every time!

So....since and while writing this email, the Comcast pop-up continues to pop up, and I still cannot reset my email account. Talk about a frustration level at this point! I would like to keep my Thunderbird email account minus the stupid Comcast pop-up. I just don't know what to do. Please help from anyone who can!

Thanks,

Michael....

Open 9 1

Delete "Weitere Lesezeichen" in sidebar

Hi, I searched the web for deleting the item "Weitere Lesezeichen" in the sidebar. I found only solutions for the firefox 85. In Firefox 85 should be a field for hiding t… (funda kabanzi)

Hi,

I searched the web for deleting the item "Weitere Lesezeichen" in the sidebar. I found only solutions for the firefox 85. In Firefox 85 should be a field for hiding this. Although in Firefox 150 it can`t be hided or deleted. I don`t need and I don`t want this "Weitere Lesezeichen". Any solutions?

Open 8

login failure on reinstalled windows desktop

I had TB on my desktop for years and finally got it also synced to my phone. Then with a failure with Windows 11 had to wipe clean the desktop and start over. Cannot re… (funda kabanzi)

I had TB on my desktop for years and finally got it also synced to my phone. Then with a failure with Windows 11 had to wipe clean the desktop and start over. Cannot reinstall TB. I obviously have the correct e-mail and password as I was able to log into Mozilla and submit this question. I believe it is a problem with my user name and what is on my phone setup does not work with my desktop reinstallation.

Open 7

Thunderbird keeps trying to install a new helper tool and never opens.

When I try to open Thunderbird it keeps giving me a message that it is trying trouble install a new helper tool and asks for my password. I do so, hit the Install Helpe… (funda kabanzi)

When I try to open Thunderbird it keeps giving me a message that it is trying trouble install a new helper tool and asks for my password. I do so, hit the Install Helper button, and then nothing ever happens. I get a spinning beach ball and it never opens no long how I wait. I would be very grateful for any suggestions or advice on what to do.

Open 7 18

Filter Problem

Hi, On one of my accounts I have an enabled filter for incoming messages consisting of a Tag + Copy + Delete (see screenshot) When a new message arrives, the filter is ex… (funda kabanzi)

Hi,

On one of my accounts I have an enabled filter for incoming messages consisting of a Tag + Copy + Delete (see screenshot) When a new message arrives, the filter is executed TWICE (see screenshot of the log) , the copied message arrives TWICE at the destination (once tagged, once NOT tagged). In the deleted folder of the source there is only one message.

What might be gong on ? Why is the filter executed twice ?

PS : I also tried Tag + Move instead of Tag + Copy + Delete

Open 6

Snooze tabs not working after update, suggestions please?

Hi all, After the last update the former Mozilla Test Pilot "Snooze Tabs" isn't working for me any more, I tell a tab to snooze and it just stays where it is. https://add… (funda kabanzi)

Hi all,

After the last update the former Mozilla Test Pilot "Snooze Tabs" isn't working for me any more, I tell a tab to snooze and it just stays where it is. https://addons.mozilla.org/en-GB/firefox/addon/snoozetabs/

I've tried running with addons disabled and then running with addons active again and the behaviour is the same. It's the same behaviour whether I run from the toolbar or the context menu.

I'm presuming this problem is related to Firefox update mechanics. Any suggestions for how to get this working again please?

Cheers :)

Open 6 2

Why does FF close without warning and wipe out the windows and tabs that were open when it crashed?

This has happened randomly on several different computers, both windows and ubuntu linux. It just now happened on my Win 11 computer. Was viewing the CNN news site and FF… (funda kabanzi)

This has happened randomly on several different computers, both windows and ubuntu linux. It just now happened on my Win 11 computer. Was viewing the CNN news site and FF suddenly closed, without a "FF crashed..." message.When I clicked the icon to reopen it, it came up with the home page group of tabs instead of reopening the windows and tabs that were opened when it crashed. Worse, none of the previous months of history shows up and recently closed tabs and windows are both greyed out.

Is there a way of recovering the history of what I was working on at the time of the crash and what the hell is causing this? I am close to dumping FF and going with something else as this is highly annoying.

Open 6

How to bypass SEC_ERROR_REUSED_ISSUER_AND_SERIAL error for local devices

I'm reposting a question already opened here because a moderator suggested to do so. Actually I though I was posting to the international forum from the URL... I was tryi… (funda kabanzi)

I'm reposting a question already opened here because a moderator suggested to do so. Actually I though I was posting to the international forum from the URL...

I was trying to access a local HTTPS website of an embedded device (a Siemens S7-1500 PLC) that is using a self-signed certificate, but was unable to go on (attached image #1, in Italian language) due to the the SEC_ERROR_REUSED_ISSUER_AND_SERIAL error. I've browsed a similar PLC webserver in the past, so the fact that the device exposes a similar certificate serial number is not so strange for me, considering also it's self-signed.

The problem is that I cannot follow the instructions of the Mozilla knowledgebase here because I'm not able to identify the correct certificate of the website!

In the attached image #2 you can see that the connection is detected as not encrypted, I suppose because only the form part of the HTML that is posting the data using HTTPS while the rest is using HTTP, but I'm not sure. If I click on the padlock icon (attached image #3) the info about the current certificate is not displayed.

Then I went into Tools > Options and searched for "certificates"; as you can see in the attached images #4 and #5, neither in the Servers tab nor in the Authorities tab I can find any item that is related to 192.168.10.2 (the webserver IP address) or Siemens (the embedded device manufacturer). But unfortunately the error persist! Initially there was a 192.168.10.2:443 line in the Servers tab and I removed it and restarted Firefox, but it didn't solve, so at the moment the situation is the one depicted by the attachments.

I had to use Microsoft Edge to access the website, but I would like to solve this issue and use Firefox instead. Is there anything else I can do to bypass the error? Why doesn't the error page provide a way to correctly identify the wrong certificate using its fingerprint and/or name? Or, maybe, is there a way to disable this check for local IP addresses or for items in a whitelist?

Thanks for your help.

Open 6

Sending Tabs to a Linux Desktop causes that Desktop to freeze

Whenever i send a Tab from any Device to a Linux Desktop, the Linux Desktop is almost guaranteed to freeze. It doesn’t matter if that Linux Desktop is my "Dingus" PC with… (funda kabanzi)

Whenever i send a Tab from any Device to a Linux Desktop, the Linux Desktop is almost guaranteed to freeze. It doesn’t matter if that Linux Desktop is my "Dingus" PC with 2GB RAM and Wayland, or my "Workstation" PC with 16GB RAM and X11. On both Desktops, Firefox runs smoothly until it gets sent a Tab from another Device, then the whole Linux Desktop freezes. The Desktop doesn’t slow if i open the Tab on the Desktop in the “Tabs from other Devices” Sidebar instead.

Only my Linux Desktops freeze when they get sent a Tab from another Device. Android doesn’t slow when my Phone gets sent a Tab from another Device.

Open 5 153

Download panel sorting

Firefox 150.0.1 Ubuntu 22.04 Problem: When downloading a file from a web page, the list of files and folders in the Download Panel are sorted such that file names and fol… (funda kabanzi)

Firefox 150.0.1 Ubuntu 22.04

Problem: When downloading a file from a web page, the list of files and folders in the Download Panel are sorted such that file names and folder names are intermingled, rather than the "standard" folders first, then files.

Discussion: This problem has been happening for a bit now (probably 2 - 3 months or more). Unfortunately, I don't recall exactly which version of Firefox this originally showed up in. At some point recently, the default sort for the Download Panel changed, so that instead of listing folders at the top of the list of download targets, then listing files, now all items are interspersed. For example, previously selecting to download a file from a web page would give the Download Panel contents as:

AFolder BFolder CFolder AFile.txt BFile.pdf CFile.jpg

Now, the list presents as:

AFile.txt AFolder BFile.pdf BFolder CFile.jpb CFolder

I would like to go back to the previous sorting behavior, but I cannot find a way to do this. I have searched the Mozilla help articles without turning up relevant information, and I have searched the internet for web sites that might list relevant information, but either the information I am seeking is not out there (unlikely) or I am not coming up with search terms that locate the information (much more likely).

I am not even 100% sure that this is a Firefox problem (it is within the bounds of possibility that it is an OS problem), but none of my other regularly used programs show the symptom, so it would seem odd to me for it to be something other than a Firefox problem.

I would appreciate any pointers (web pages, help articles, or even just "change this in about:config) on how to resolve this.

Open 5 45

Tab crashes

Bruce Caress May 7, 2026, 15:17 CST Hello, I've been watching MSNOW at 4pm eastern and after about half an hour it crashes. I get a message to send a report and restore t… (funda kabanzi)

Bruce Caress

May 7, 2026, 15:17 CST

Hello, I've been watching MSNOW at 4pm eastern and after about half an hour it crashes. I get a message to send a report and restore the tab. I restore the tab which works for maybe ten minutes and crashes again. I am using Windows 11 on a new computer. I'd appreciate some assistance. Thanks. Bruce Caress

Moderator note: This question has been edited to precise Firefox and OS version, based on the crash reports.

Open 5 1