Thunderbird Community Forum

Hello,

I have this problem. On only 1 PC from 5, with same mailboxes installed and same configurations, on one of the mailboxes, Thunderbird does not accept setting to "not read" the letter. I tried making time to read the letter and it worked for 10 min, and then again stopped. At final, no matter how it is set, when I push to read the message it always read it.

Tried repairing the folder, but doesn't work.

Any Ideas will be great.

Thank you

[I was sure I submitted this but I can't find it. Sorry if it's a dupe.} Thunderbird v. 151.0 (64-bit) Windows 10

When I reply to or forward a message, I get raw code like:

> ad that says: Mary gets us <https://click.ngpvan.com/

> k/132163625/623609951/778722144?refcode=LOC_EM_FR_2026.05.27_peltola-

> split_B1_F1_S1_C1_60DO90DC120DD_N-

> T0&nvep=ew0KICAiVGVuYW50VXJpIjogIm5ncHZhbjovL3Zhbi9OR1AvTkdQMTkvMS83MjcyMiIsDQogICJEaXN0cmlidXRpb25VbmlxdWVJZCI6ICJlYTIyODEwZS1kYzU5LWYxMTEtOGZjYi0wMDBkM2ExODkwNWMiLA0KICAiRW1haWxBZGRyZXNzIjogImhvb2V5Z29vQGdtYWlsLmNvbSINCn0%3D&hmac=FH6VuhfY9AcHmAdMj2RHECp0IpRhxQHb41JBnp34fM0=>

>

How can I get just the normal readable text quoted (Gmail-style)?

TIA

The oversized menu box cuts off the the "Save" key and I can't re-size the Message Filter/New Filter box nor can I slide it up for access to the button on the very bottom. Windows 10 Home, Version 22H2, Installed on 9/14/2021, OS Build 19045.6466.

I've tried a dozen fixes suggested by Duck AI and none had any effect on the Filter box. Here’s a concise list from Duck AI of every fix I tried:

   Hold Shift while opening the Filter menu (compact popup).
   Shorten long filter names (Tools > Message Filters).
   Change system UI scale (Windows Display scaling).
   Toggle toolbars / layout to reclaim space (View > Toolbars / Layout).
   Use Tools > Message Filters dialog (resizable) instead of the menu.
   Add userChrome.css rules (multiple variants) in profile/chrome/userChrome.css to force max-height, scrollbars, reduced font/padding:
       Generic menupopup rule (max-height: 420px, font-size: 11px).
       Targeted rule including .filter-menu-popup and #createFilterFromPopup (max-height: 300–520px, font-size: 10–11px).
       Final variant replacing values with 360px (no effect).
   Attempted diagnostics via screenshots and Developer Toolbox (Ctrl+Shift+I) — determined screenshots showed Filters dialog, not popup.
   Determined the "Create Filter From" list is likely a native Windows popup (userChrome.css cannot style).
   Workarounds proposed:
       Use the resizable Message Filters dialog to create filters manually.
       AutoHotkey script (Ctrl+Alt+F) to open New Filter and pre-fill From/To/Subject from the selected message (provided full script).

I had received several emails from an individual over the past few weeks. All emails displayed in the inbox (on my desktop computer) as they should. This afternoon suddenly all of these emails disappeared from the desktop inbox. The emails are still on the server and are and can be viewed in the inbox on my laptop but not on my desktop. If I use the quick filter function in the desktop the emails are there but not in the inbox. I assume some sort of filter accidentally was activated (I did not attempt any filter changes) but I can't find how to remove this filter function so the emails again appear in the inbox as they should. Please provide detailed instructions how to get these emails to reappear in the desktop inbox.

Hello,

I am on Thunderbird 150.0.2 for Windows.

I am really suffering here. I need to change the font weight of unread messages. In a non-threaded list.

The default weight I get with my preferred font (Trebuchet MS) is not bold. It is BLACK. When I say BLACK, I mean ultra bold, display font, heading weight. Heavier than the boldest font that even exists in the font family. Thunderbird is creating this ultra mega black font by taking the bold font variant and applying a faux bold effect to it. The result is that the text is so heavy that it takes up twice as much horizontal space as the ordinary bold font variant. This becomes a usability issue because it's not possible to see the date, sender, and subject at the same time.

I have struggled and strived with userchrome.css. Spent hours combing through forums here and elsewhere. I've already enabled the mystery setting in the config editor. I put userchrome.css where it is supposed to be.

I saw a blog post from Mozilla that says "userchrome.css is not supported". What is the actual meaning of this? That it has been actively blocked from working anymore, ever, for anyone? Or that users are taking risks if they create userchrome.css? Why can't developers speak plain language? "Not supported" could mean many things.

When I go to the Style Editor, userchrome.css does not exist there. Which leads me to believe that user customizations are absolutely deprecated and we are not permitted to use userchrome.css.

I tried editing some of the rules in the Style Editor, but could not determine any way of actually storing the changes. When I click Save, I get a dialog where I can **EXPORT** the file. But I can't seem to actually save the changes, because CSS files do not appear to exist in the installation directory. It must be compiled into some library.

This is extremely unsatisfying and super frustrating. Just getting straight answers to things is super difficult, nothing stays the same for more than a couple months, and up to date information either does not exist or is not found by any search engine.

So, please help. I just need to change one setting, the font weight of unread messages. Since Thunderbird is allegedly open source, I thought I would have some ability to make such changes. But the Style Editor doesn't seem to actually be an editor, but merely a read-only interface to precompiled rules? If I wanted to change the font weight of unread messages, would I be forced to compile my own version of Thunderbird? I'm not competent to do that, and it would probably either prevent updates, or the updates would break my changes.

Please help, I am super desperate. I need to see the date, sender, and subject all at the same time. That doesn't seem like an unreasonable ask.

I would gladly pay for an email client that gives me control over my data *and* allows me to control the UI, but apparently that doesn't exist.

Earlier in the year I installed Thunderbird onto a new PC having previously used an older version on an older PC. When visiting a web site (and clicking on an email hyperlink there) my previous version used to automatically launch Thunderbird but the new version doesn't do that any more (i.e. clicking email hyperlinks doesn't do anything at all)

I'm running on Windows 10 and using Thunderbird version 150.0.2. I this likely to be due to some setting in Thunderbird? Or is it maybe something I need to configure in Windows?

I've been using Thunderbird for about two months now and I just realized that Thunderbird (150.0.1) seems to be unable (or unwilling) to use some of the fonts that are on the computer (Windows 10, plenty of RAM and disk space).

Let me explain that I don't send a lot of emails, and most of the ones I do send are just a few lines so I had not had any reason to bother with the font -- the default font was fine -- until today...

Today my experience with fonts in Thunderbird was extremely disappointing. It started when I was composing an email and I copied/pasted some text from a web page into the email. Rather than treating the pasted text as simply text to have in the default font, Thunderbird put it in some strange font and size. This might have been Thunderbird's attempt to use the font from the website but neither the font nor the size resembled the text that I had copied/pasted. That was when I noticed that Thunderbird does not let you choose the actual size but only offers the choice to make text larger or smaller. Making the text smaller was sufficient for that particular time.

As I finished the email, I tried to sign my usual signature. Thunderbird lets you choose the font but once I had chosen the font that I routinely use for my signature, I discovered that Thunderbird totally ignores the choice that it just let you make. Instead of displaying the signature in the chosen font, it displayed my signature in a plain sanserif font.

I could live with a limited choice of fonts -- I have used another program where the only choices were serif and sanserif -- but I cannot understand why Thunderbird would offer a font choice menu that includes all my installed fonts when it actually only honors three choices. The only fonts reliably used seem to be some generic sanserif font that Tunderbird calls Helvetica/Ariel, a generic serif font that it calls Times and another serif font it calls Courier.

The dropdown menu lets me choose any of the fonts I have installed, some of them display properly while composing the email, others don't. If I send the email to another of my email addresses, Thunderbird displays the text the same way -- some fonts are correct and some fonts get replaced with one of Thunderbird's generic fonts.

I'd really like to have all my fonts available -- but that doesn't seem to be possible with Thunderbird so I guess I need to figure out which fonts Thunderbird is willing to use.

In Thunderbird, how can I stop text in the previous emails in a string turning blue?

I have looked everywhere in Settings where colour is mentioned and everything is set to black text on a white background. Nothing is set to blue.

I do not want to see blue text anywhere.

Please advise.

Since updating Thunderbird 64 bit to v147.0.2, then to v148.0 (1st March 2026, just now), requesting the display of 'Unified Folders' (in Folder Modes) does not populate the unified Inbox with messages from any of my eight registered email inbox sources. The individual inboxes with their contents can be displayed below, but not in the unified Inbox.

Since being introduced several versions ago, I have found this feature very useful when checking my various received emails, and it is frustrating to be without it.

Can anyone suggest what I may or may not be doing to get this feature to work any more? I have been all through Settings, but cannot find anything relevant to this problem.

Cheers, Sam

I've been using color settings in userChrome.css to set the colors for the threads and folder panes... I obtained these settings from a discussion in the Thunderbird Beta mailing list, back in 2023. Here are my current settings:

root {

 /* Force BG in unthemed folder */
 --foldertree-background: #A99B92 !important;
 /* Force BG in threads */
 --tree-view-bg: #A99B92 !important;
 /* Force black text in threads */
 --tree-view-color: #000 !important;

} /* Position Menu Bar above Unified Toolbar */

1. toolbar-menubar { order: -1 !important;}

However, after the most recent beta update, the tree-view settings are no longer working, and I'm stuck once again with the ghastly Bright White background... see the attached image; note that the foldertree setting is still working though...

What do I need to do, to get this code working again? or is this a bug in the current beta?

I manage 8 emails accounts for the dfferent projects - I collapse all the account folders when I close down T/B. When I reload T/B all the email account folders all open up. Is there a setting to prevent this?

I need predictability where I can find it. Thunderbird opens how I left it, so I never know what's going to appear when I start it the next day. Isn't there some setting so that it always opens showing all 3 panes, regardless of my laziness at exit? It would also help with my autohotkey script if it knew what to expect. I suspect the lack of answers in my search suggests there is no such setting. How about a command line argument?

I'm new to Thunderbird and am having a problem when printing emails. The page to be printed, when shown on the initial screen as well as when actually printed, starts with a long list of technical computer-related data which, in the case of new Inbox emails, takes up about 1 1/3 at the outset of the printed pages, even if the email message itself is very brief. Even when I click off "print using system dialog" at the bottom of the Print menu, that technical data (though no longer shown on the initial screen) is still included when printed.

I can't find a solution in the online help files.

Thanks for your help in trying to resolve this,

John