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Increase font sizes for specific UI elements using CSS, still possible?

I tried following the instructions in this archived thread: https://support.mozilla.org/mk/questions/1269283

The instructions for changing layout.css.devPixelsPerPx (by going into Preferences, searching for config, and choosing "Config Editor") do work to change the scale of everything in Thunderbird.

I still don't like the relative sizes of things, though, and would like to change the elements individually. Specifically, the general UI text is too large compared to the message list and folder hierarchy.

The instructions for editing the userChrome.css file do not seem to do anything. Is there any other way to do what I want, i.e., make the message list and folder hierarchy larger without increasing the size of the rest of the UI?

I tried following the instructions in this archived thread: https://support.mozilla.org/mk/questions/1269283 The instructions for changing layout.css.devPixelsPerPx (by going into Preferences, searching for config, and choosing "Config Editor") do work to change the scale of everything in Thunderbird. I still don't like the relative sizes of things, though, and would like to change the elements individually. Specifically, the general UI text is too large compared to the message list and folder hierarchy. The instructions for editing the userChrome.css file do not seem to do anything. Is there any other way to do what I want, i.e., make the message list and folder hierarchy larger without increasing the size of the rest of the UI?

Chosen solution

Try this:

/* Threads Pane*/
#threadTree > treechildren {
  font-size: 12pt !important;
  font-family: Times !important;
  background-color: lightgrey !important;
  color: navy !important;
}
/* Folder Pane*/
#folderTree > treechildren {
  font-size: 12pt !important;
  font-family: Times !important;
  background-color: lightgrey !important;
  color: navy !important;
}

Help/More Troubleshooting, Profile Folder, Open Folder, close TB, create a new folder named chrome, create a new document in chrome with a text editor, name it userChrome.css, Save as type: All files *.*, copy in the above code, change the colors and numbers as desired. Double-click toolkit.legacyUserProfileCustomizations.stylesheets to true in Preferences/General/Config. editor, restart TB.

To apply the font-family setting, 'Allow messages to use other fonts' must be checked in Preferences/General/Language & Appearance, Advanced.

Read this answer in context 👍 1

All Replies (2)

Chosen Solution

Try this:

/* Threads Pane*/
#threadTree > treechildren {
  font-size: 12pt !important;
  font-family: Times !important;
  background-color: lightgrey !important;
  color: navy !important;
}
/* Folder Pane*/
#folderTree > treechildren {
  font-size: 12pt !important;
  font-family: Times !important;
  background-color: lightgrey !important;
  color: navy !important;
}

Help/More Troubleshooting, Profile Folder, Open Folder, close TB, create a new folder named chrome, create a new document in chrome with a text editor, name it userChrome.css, Save as type: All files *.*, copy in the above code, change the colors and numbers as desired. Double-click toolkit.legacyUserProfileCustomizations.stylesheets to true in Preferences/General/Config. editor, restart TB.

To apply the font-family setting, 'Allow messages to use other fonts' must be checked in Preferences/General/Language & Appearance, Advanced.

Modified by sfhowes

Yes, thank you, that works great. I'll do a little tweaking but that's exactly what I was looking for.