SquirrelMail remove the H1 tag when displaying the email.
If I save it to file and look at it, the H1 tag is in.
If I view the email in SM and click on inspect element then the H1 tag is not there.
I will attach all files needed to see what I mean:
mail-saved-from-squirrelmail.html - save from SM when viewing th email
screenshot-squirrelmail.png - screenshot of email in SM
screenshot-yahoomail.png - screenshot of email in YahhoMail (how it should appear)
screenshot-gmail.png - screenshot of email in GMail (also looks correct)
squirrelmail-configtest-output.txt - for helping with debug
mail-source.txt - source of mail saved from GMail
Some info for debug...
SquirrelMail version: 1.4.15
Installed plugins: sorry, I do not know.
PHP version: 5.2.6-1+lenny16 (CGI/FastCGI)
Web server: Apache 2.2.9
IMAP server: sorry, I do not know.
SMTP server: Postfix (Debian/GNU)
OS: does not matter
Browser: does not matter
Error message: none