270287 - user font preferences do not apply to UTF-8 messages

Status: VERIFIED INVALID

(Thunderbird :: Preferences, defect)

Description

[Mikel Ward]

For some reason, plain text messages which specify the UTF-8 character encoding
are displayed in a larger font than all other plain text messages (ones using
encodings such as ISO8859-1).

An example plain text message I received was generated by KMail/1.7 and included
these headers which might be relevant:
User-Agent: KMail/1.7
MIME-Version: 1.0
Content-Type: text/plain;
  charset="utf-8"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

I have seen this many times, in many different Thunderbird builds (most recently
0.9 release), but presumed it was a problem with my Linux install and
fontconfig, however I'm also seeing this on Windows 2000.

I'm using the following settings:
DISPLAY
Wrap text to fit window width: Yes
Display emoticons as graphics: Yes
Use the following font: Variable width font

FONTS
Proportional: Sans Serif (12 pixels)
Serif: Bitstream Vera Serif
Sans-serif: Bitstream Vera Sans
Monospace: Bitstream Vera Sans Mono (12 pixels)
Display resolution: 96 dpi
Minimum font size: None
Allow messages to use other fonts: Yes
Outgoing mail: Western (ISO-8859-1)
Incoming mail: Western (ISO-8859-1)
Apply default to all messages: No
Always use the default character encoding in replies: No

Comment 1

[Mikel Ward]

Pretty much seems to be whenever a message is handled as UTF-8 that it looks wrong:

1. Changing fonts to (Georgia, Tahoma, Andale Mono) exhibits the same problem
2. Changing from variable width to fixed width exhibits the same problem
3. Other messages specifying a "utf-8" encoding, such as those generated by
   Red Hat's Bugzilla, but not necessarily having the same User Agent or
   any MIME headers, also exhibit the same problem

After forcing all messages to use my specified character encoding by enabling
the "Apply default to all messages option" and then:
1. Setting the default incoming mail encoding to Western (ISO-8859-1)
   causes all messages to be rendered at the correct (expected) size
2. Setting the default incoming mail encoding to Unicode (UTF-8)
   causes all messages to be rendered at the incorrect (larger) size

In case it's relevant, the system where I'm current seeing this problem is
Windows 2000 using the English (Australia) locale.  Most of the BSD/Linux
systems I use would have a locale such as en_AU.UTF-8.  I say this just in case
it only exhibits itself where the user's default character encoding is UTF-8 (or
some Unicode variant such as UCS-2, if that's what Win2k uses).

Comment 2

[Mikel Ward]

Okay, I decided to confirm my allegation of "correct" versus "incorrect".  I
have discovered there are two major problems (or at least one significant
problem and one area where the application differs from expectations).

Compared to other applications such as Microsoft Word and Notepad (the first two
comparison points I could think of), Mozilla Thunderbird is rendering the fonts
incorrectly: when I specify a standard font size of 12 points, I am actually
getting the same rendition other applications would provide using a font size of
10 points.  In other words, I've got to ask for a larger size in Thunderbird
than I really want.

The second problem is that as I scale my default font size downward, messages
encoded as iso8859-1, us-ascii, etc. all behave, but messsages encoded as utf-8
continue to be displayed in the same, larger, font size (about 12 points in real
terms or 14 points in Mozilla's configuration).  I therefore conclude that the
user's font preferences are not respected for messages encoded in UTF-8.

Comment 3

[Matthew T (active 1999-2002)]

In Thunderbird, you can set different font prefs for each encoding. The encoding
you are altering the prefs for is selectable from the "Fonts for:" menu at the
top. Did you set the same font prefs for both Western and Unicode?

(Worksforme, Thunderbird 1.0, Ubuntu Hoary 2005-03-03.)

Comment 4

[Mikel Ward]

Oops!  I didn't even notice the encoding list.

Thank you Mozilla and MPT for welcoming me to the internationalized world. :-)

-> INVALID

Comment 5

[Matthew T (active 1999-2002)]

Verified. I designed the font prefs interface, and in retrospect it is too
complicated, but this bug in particular is not my fault. For details, see
<http://groups.google.co.uk/groups?selm=3B83CD22.652BF353%40mailandnews.com>.

Comment 6

[Benjamin Esham]

*** Bug 305430 has been marked as a duplicate of this bug. ***

Comment 7

[Mikel Ward]

Note that the Unicode entry is now called Other Languages.