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How to view messages with larger font

  • 3 replies
  • 2 have this problem
  • 7 views
  • Last reply by Zenos

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I am using Thunderbird 52.7.0 64bit on Linux. I've set Edit > Preferences > Display, all font sizes to a larger font, including in the Advanced dialog. However, I don't see these settings having any effect when reading messages. They all remain small.

I do see the size change if a message is sent from mailx which does not html encode the message. For html encoded messages, e.g. those sent from Thunderbird, an examination of the html shows "<font face="Calibri">", but I see no font size information at all.

Do the Preferences > Display font settings get ignored for html encoded messages? </font>

I am using Thunderbird 52.7.0 64bit on Linux. I've set Edit > Preferences > Display, all font sizes to a larger font, including in the Advanced dialog. However, I don't see these settings having any effect when reading messages. They all remain small. I do see the size change if a message is sent from mailx which does not html encode the message. For html encoded messages, e.g. those sent from Thunderbird, an examination of the html shows "<font face="Calibri">", but I see no font size information at all. Do the Preferences > Display font settings get ignored for html encoded messages?

All Replies (3)

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Go back to the font size settngs and repeat your adjustments for font sizes for both Latin and Other Writing Systems.

Modified by Zenos

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I did this and it changed the size of font in the actual message, but not in the list of messages received. Font is so small there it's hard for me to read.

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The usual solution for this is to install the Theme Font & Size Changer add-on. However some time ago its author indicated that he would be dropping support for Linux. On op of that, recent versions have come with a timebomb that disables the add-on after some pre-set date.

As a Linux user myself, I use a userChrome.css file. But first of all, check if your system DPI is correct. Most operating systems, including Linux distributions, default to 96 dpi, but on a modern machine you may have a higher resolution than this. Here I have 143 dpi, and in Linux you can generally set this explicitly; other (inferior) Operating Systems have a silly slider control where you tweak until you're happy. I usually have to set Windows to 125%.

Getting the DPI setting right will enlarge just about everything.

If you're still uncomfortable with the menus and lists n Thunderbird, then you can try one of these:

  1. In the config editor, adjust layout.css.dpi. This can be set to the exact DPI for your screen. -1 signifies use the system default, i.e. that via your desktop settings. This setting is only available in the Linux version.
  2. There is a similar setting, layout.css.devPixelsPerPx which does much the same, but here you'll want a value between, typically, 0.95 and 1.5. Again, -1 means use the default. Essentially, this is doing something akin to that percentage tool that Windows offers. You can imagine that 1.5 means 150%.
  3. Finally, the third option is to create a folder named chrome in your Thunderbird profile. It's important it's all lowercase. In that folder create a text file named userChrome.css (again, the exact case is important) and in that file, place the following text:
/*
 * Do not remove the @namespace line -- it's required for correct functioning
 */
@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* set default namespace to XUL */
/* Make all the default font sizes 13 pt. */
* {
    font-family: "Liberation Sans" !important;
    font-size: 13pt !important;
 }

You can omit the font-family line if you don't want to set the font typeface.

You can adjust the font-size line to whatever suits you. You can use pixels (px) or ems (em) if they are more familiar.

You can use a similar file, named userContent.css to set a default font size for the text of your messages.