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Font size

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  • Last reply by Toad-Hall

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Thunderbird 78.12.0 fonts (on menus, folders, etc) too small. All answers I find for previous versions list menus that do not exist in this version. How do I enlarge the systm fonts on this higher resolution screen?

Thunderbird 78.12.0 fonts (on menus, folders, etc) too small. All answers I find for previous versions list menus that do not exist in this version. How do I enlarge the systm fonts on this higher resolution screen?

Chosen solution

If you want to increase the font in everything then do this:

  • Menu app icon > Options/Preferences > General
  • Scroll down to the very bottom
  • click on 'Config Editor' button to open 'about:config'
  • Accept the risk.
  • In search type: pixels
  • Look for this line: layout.css.devPixelsPerPx
  • Double left click on that line to open the 'Enter string Value' box so you can edit the Value.

The default value will be a negative number: -1.0

  • Enter a new positive number eg: 1.25 or 1.5 or 2.0 or 2.2
  • click on OK

the effect is immediate, so you can modify that number until it looks ok for you. Image below as guide.

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Chosen Solution

If you want to increase the font in everything then do this:

  • Menu app icon > Options/Preferences > General
  • Scroll down to the very bottom
  • click on 'Config Editor' button to open 'about:config'
  • Accept the risk.
  • In search type: pixels
  • Look for this line: layout.css.devPixelsPerPx
  • Double left click on that line to open the 'Enter string Value' box so you can edit the Value.

The default value will be a negative number: -1.0

  • Enter a new positive number eg: 1.25 or 1.5 or 2.0 or 2.2
  • click on OK

the effect is immediate, so you can modify that number until it looks ok for you. Image below as guide.