On utilise un programme annexe: MsgCvt : http://www.elbiah.de/tools/index.htm, http://www.geckozone.org/forum/viewtopic.php?t=31593
J'ai fait un .BAT pour simplifier la procédure: http:// tayeb.fr/informatique/Msgcvt_GT.zip

<br>
<br>
<hr color="#000000" size="1">
<font color="#000000" face="Tahoma" size="2">
<b>Subject:</b> %subject%<br>
<b>Sent:</b> %datelocal% %date_tz%<br>
<b>From:</b> %from%<br>
<b>To:</b> %to%{<br>
<b>Cc:</b> %cc%}</font>
<br>
<br>

As far as I know, Stylish or Stylus no longer work in Thunderbird.
Access your Thunderbird profile folder;
create a folder named "chrome";
inside this folder, create a text file and rename it "userChrome.css";
create another text file and rename it "userContent.css".
In the userChrome.css file put your CSS code to change the appearance of Thunderbird and in the userContent.css file put your CSS code to change the appearance of elements of Thunderbird internal pages.

I found an old copy of the settings I had made in the old Stylish add-in and put them into userChrome.css -- I actually tried user.Content.css first -- and they work exactly as they did before!! xD
I'm so glad I found that copy, bc if I'd have had to invent all those entries, I'd never have managed.

https://j2m-06.pagesperso-orange.fr/faq_tb_userchrome2.html#UC_modi_coul_CCa

Code du fichier userChrome.css :
/*Modifier la couleur du texte de : Copie cachée à - ok TB60 et TB78 */
   #expandedbccLabel {
        color: yellow !important;
    }

There is a bug in Windows Vista, Windows 7, and Windows 2008 where the last modification date & times of .eml files are changed. To fix this you must delete the following registry key:
\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\PropertySystem\PropertyHandlers\.eml
Note that to do this you should run regedit.exe as Administrator. You may also need to change the keys permissions to delete it (right click on the .eml key entry and choose Permissions, then Advanced, set the owner to the current user or Administrators, then check the Allow box for Full Control for the permissions of Administrator and click OK).
Also be aware that if you re-install Windows Live Mail then it will recreate this registry key and so the problem will occur again. If you do re-install Windows Live Mail then you must delete the registry key again.
Applies to: Windows Vista, Windows 7, Windows 2008