Thunderbird Community Forum

Until today Oct 14, 2025 I could edit the subject line on my incoming e-mails by right clicking the subject line and use 'edit subject'. As of this morning that option is not available in the context menu that comes up when I right click the subject line for an e-mail in my inbox. anybody have any ideas? I use this function constantly in my business to add the customer name to the subject line for customer searches and if I send a copy to a vendor so all messages pertaining to that customer are easily found.

I can't find where to edit the rules that I previously created for what will happen when a certain mail comes to my mailbox. I set up a rule that marks a mail from a certain sender with "Important" and also sends a copy to another mail adress but now I can't edit the rule. Can someone help me with where I can find the rules and edit them?

Others have mentioned this but I'm not sure if there is a fix/anything is being done. The threads are all from previous Thunderbird versions.

I use Thunderbird for work. I have to find specific emails and folders - get to them quick. I am no longer able to do this. It's really distressing.

This is something really basic, that should be the default or else really easy to change.

I'm on a Windows machine and using Thunderbird 140.3.0esr. I've been using Thunderbird since 2003 and never had any problems. Now I'm panicking!

I have 1 computer that shows bars at the top and left side that I like. The one at the top shows Get messages, Delete, Reply, Reply All, and a few more items. The one on the left side shows icons that are for Mail, Address Book, Calendar, Tasks, and Chat. I have another computer that doesn't have those bars. I have attached a screen shot from that computer. Both are running T'bird 140.4.0esr (64-bit) and both are Win 11 machines. I've tried everything I can see to get the 2 bars to appear on the 2nd computer. I hope someone can tell me how to get them to show up. Thanks, Mike

I use Thunderbird for my emails on a Windows-Desktop. I still run Windows 10 as the computer is too old to upgrade to Windows 11 and I have signed up for the extended Maintenance.

In Thunderbird I have set up filters to organize my mail. When I wanted to change one of my filters a few days ago, I was not able to do so, as my Menu in Thunderbird doesn't show the ->Extra Option any longer. My Thunderbird-Version is up to date (140.4.0esr (32-Bit))

Any idea, how I can access my filters and maintain them again?

Thanks for your thoughts and your support

I recently transferred my Thunderbird email to a new Windows 11 laptop. Everything is ok, except the font size in received emails can best be described as very tiny. I've tried everything to increase the font size, but nothing helps. My screen has a resolution of 2880x 1880 Any help would be much appreciated. Thanks.

Hi, lot of years ago I have changed TB to use maildir ibstead of mbox for new accounts, Now I met some filtering issue I can't fix and it is proabely caused by maildir.

So I'd like to set TB to use mbox with new accounts instead of maildir.

Some additional info: TB 144.0.1 (64 bit), win 10 pro, I have 4 mbox accounts and one maildir account.

There is no need to export / import / keep data existing on maildir account. I can remove it with no pain. I just want to setup TB to create new accounts as mbox again.

Any help will be appreciated.

TIA

Is there a way to make the “Today” tile stand out more clearly in the calendar month view? The currently selected day is displayed with a light gray background and stands out, but the actual day is only modestly marked by the day number. With many entries in the calendar, it is therefore difficult to recognize. I would therefore like to see a user-selectable background for the current day.

I am running Windows 11 with Thunderbird V144 and the Windows Classic theme. I find the background colors of the Message List Pane and the Message Pane almost the same as background of the Header pane. I would like to change the background color of the Header Pane so that it stands out more. I looked on the internet and found some solutions to most other Header Pane features but not the background color. Most of those solutions were additions to the userChrome.css file that appear not to work on V144.

I would appreciate some help with this.

When I read a message, the subject line font is larger than the other headers. Is there a way to make it smaller?

Win10 Betterbird 140.4.0esr-bb13 (64-bit)

thunderbird email program does not have a "go to inbox" option. The program automatically creates tabs, and sometimes I need them. If so, it takes up to a minute to press the back button to go back all the way through them to the inbox tab. Why cannot mozilla thunderbird supply a go to inbox tab so I can go back to the inbox directly?

I don't really need to talk to a "volunteer". This is a question for whoever writes or engineers the thunderbird product. We should be able to send such questions and requests to those people who write and design this product. Does any "volunteer" know how to contact the needed personnel to redesign the product so it offers what I need?

In the recent update Thunderbird 140.4.0 esr , the fonsife of the folder names is noticeably smaller....which makes the folder name appear to be "scrunched up"....very close together. I cannot find a way to increase that font size.

The other side with email correspondents and subjects is fine...the increse of the font size there is easily done. I have attached a screen shot of the list of folders.

I simply wish to increase their font size so it separates the vaarious names and thereby increases the font size used there.

Brian

HI.

I'm trying to increase the size of the text-entry pane that appears in the calendar event editing pop-up. I already know how to change the size of the overall window (i.e., the pop-up itself), but I can't determine the name of the css element that would modify it.

I enabled developer tools, but the Inspector function doesn't seem to want to provide the name of that css element. It would be along the lines of calendar-event-pane, but that's not it.

Is that text window even specified in css, or is it hard-coded?

Any pointers would be appreciated

I'm transferring to a new computer. The old computer is using version 140.4.0esr (yet it says it's up to date, when the other computer is using 144.0). I have 2 e-mail accounts setup, so the left panel is a little longer. In the old version that left panel that shows all the folders is 100% the height of the window. On the new one, the bottom panel which has the e-mail in it (preview at the top) takes up 100% width of the window. I need that left panel to be 100% height, and then the preview panel with the e-mails listed at the top (which it is) and the panel at the bottom that shows the e-mail at the bottom to fill up the rest of the window, if that makes sense.

I've added 2 screenshots. One for how it looked on my old computer and one for how it looks on my new computer. I want it to look like it did on the old computer.

I would also like to get the bar at the top back with the new messages, write, chat, address book, etc.

I have tried all the settings I can think of and things I've found online with no luck. Any help would be GREATLY APPRECIATED! TIA!