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Increasing font size / userChrome.css ignored

  • 2 replies
  • 1 has this problem
  • 1 view
  • Last reply by Ray

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Hi,

I am partially sighted, and having just updated to v 78.2.1, I need to increase Thunderbird's user interface font size, please.

I have spent HOURS scouring the forums, and know that I am not alone in not being able to easily do this, so kindly excuse me.

Below is the content of my userChrome.css file on my Windows 10 machine, which TBird ignores even on re-boot. I have no Add-Ons, and only one Profile.

PATH C:\Users\Ray\AppData\Roaming\Thunderbird\Profiles\xxxxxxxx.default\Chrome

[xxxxxxxx.default replaces real file name.default]

CONTENT /*

  • Do not remove the @namespace line -- it's required for correct functioning
*/

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");

/*

  • Make all the default font sizes eg:18 px:
  • /
  * { font-size: 18px !important; } 

Would you kindly advise me and explain what I am doing wrong?

Many thanks,

Ray

Hi, I am partially sighted, and having just updated to v 78.2.1, I need to increase Thunderbird's user interface font size, please. I have spent HOURS scouring the forums, and know that I am not alone in not being able to easily do this, so kindly excuse me. Below is the content of my userChrome.css file on my Windows 10 machine, which TBird ignores even on re-boot. I have no Add-Ons, and only one Profile. PATH C:\Users\Ray\AppData\Roaming\Thunderbird\Profiles\xxxxxxxx.default\Chrome [xxxxxxxx.default replaces real file name.default] CONTENT '''''/* * Do not remove the @namespace line -- it's required for correct functioning */ @namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* *Make all the default font sizes eg:18 px: */ * { font-size: 18px !important; } ''''' Would you kindly advise me and explain what I am doing wrong? Many thanks, Ray

Modified by Ray

Chosen solution

Dear Anje (Toad-Hall),

Thanks soo much for this!

Both solutions worked in fact.

Good ol Toadie : )

Best wishes,

Ray

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All Replies (2)

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re :C:\Users\Ray\AppData\Roaming\Thunderbird\Profiles\xxxxxxxx.default\Chrome

The 'Chrome' folder should be 'chrome' folder - note the spelling - no capital C

Also check this is set to 'True'

  • Menu app icon > Options > General
  • scroll to bottom
  • click on 'Config Editor'
  • Accept warning
  • In search type: legacy
  • look for this line: toolkit.legacyUserProfileCustomizations.stylesheets
  • If it says Value is 'False', double click on line to toggle the value to 'True'
  • close window - click on top right X


However, there is another method you might like to check out. The developers have now included a means of increasing pixel ratio.

  • 'Menu icon (3 lines) > Options > 'General'
  • scroll all the way down to the bottom
  • click on 'Config Editor' button

It may say 'here be dragons' as a type friendly warning to be careful :)

  • In top search type: pixels
  • Look for this line: layout.css.devPixelsPerPx

The default is -1.0

  • Double click on that line to open a small window.
  • clear contents and type in eg: 1.5 or 1.75 or 2.0 or 2.25
  • click on OK

The effect is instantaneous, so you can gradually increase the number until you find the size that suits you. This will effect all of Thunderbird.

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Chosen Solution

Dear Anje (Toad-Hall),

Thanks soo much for this!

Both solutions worked in fact.

Good ol Toadie : )

Best wishes,

Ray