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320 reviews for this add-on
  • I have used Theme and Font changer for years with Thunderbird and with all the updates Thuderbird fonts have gone extremely small as all are saying. Theme and font changer fixes this, but it wont save changes in my windows 7

  • BIG THANKS TO USER "e12884"


  • Nothing working anymore since we got the last update (10 of january 2018) ! When i uninstall the addon and re-install it ,impossible to make this module working .....nothing happens !!!

  • Absolutely indispensable for those of us with poor eyesight, but why the automatic expiration? David Ross, thank you from the bottom of my heart for providing a version that works with Thunderbird 52.

  • Well, it took two hours, but I finally found a version that works with the new Thunderbird update. roll on back to TaFSC 46.5, and your eyes will stop bleeding!

  • Doesnt work...people like me who are getting older and eyes needing seems you didnt take account of us when the 56 theme and font was great and now that wont even work. Firefox for every update makes your browser worse. Get some common sense and do it right.

  • Although it doesn't work with current versions of Firefox I used an older version and can now see the menus again. (I have a large screen monitor). I hope you and Firefox come up with a new version that works soon. Thanks!

  • I downloaded the file for tfasc which anonymous wrote on here then went to my extensions in firefox addons, on the settings it asks if you want to install addon from file and it installed immediately now I can see the menus better, mind you I did not upgrade to firefox 57 I kept 56, and I will not upgrade to 57, at least I have theme, font and size changer back on my laptop and I have version 56 of tfasc

  • What's always going on with these Baris Derin addons ?
    Suddenly TFSC no longer works on TB

    What's the latest version working on TB 52.5.2 ?
    Where can I find old versions of Addons ?

    It's a pity things are being messed up so frequently (partly initiated by Mozilla and it's Web-Extentions hype)

  • This is a great ad-on, when it is not being updated. It suddenly disappears from the toolbar menu, and all settings with it. So you have to go search for an update.

    THIS time (Jan 8, 2018) it seems it's broken, and cannot be fixed.

    Shoddy programming, really.

  • Unfortunately the mediafire version only worked for a day for me. I found the following on Mozilla support though and it worked fine for me:
    (1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button accepting the risk.

    (2) In the filter box, type or paste pix and pause while the list is filtered

    (3) Double-click layout.css.devPixelsPerPx and change its value to 1.25 and click OK, which corresponds to 125% font size in Windows display settings. The toolbar area should enlarge after a few moments. Too small? Try 1.5 and see whether that suits you better. And so on. If you are on Mac and use a Retina display, anything below 2.0 may be smaller than what you started with, so start with 2.0.

  • Many thanks Binjohn for this fix! Is there any fix for comodo icedragon too?

  • @Anonymous user 6f91c8

    Fantastic! It works! Thank you very very much, comrade.

    Working on Firefox 56.0.2 (64-bit) :)

  • I am now using Waterfox so that I can use my Firefox add ons. My eyesight is poor now and theme font & size changer is essential for me. However since yesterday I have tried all the versions to download and then turned off automatic updates. The icon is showing in the toolbar, but the problem I have is that when I open the theme font context menu it is not showing any fonts and every time I click on anything it comes up with a box showing Javascript Application TypeError:.

    I don't if anyone has any idea what the problem is as without this add on I am going to really struggle to use the internet.

  • Worst day of my life... this mourning Thunderbird on my both MACs has been automatically updated and now this Addon in not working. Tried to roll back to the old version but that does not helped. My eyes are bleeding when I reading my Emails folders (((
    Please help me, love Thunderird, but my eyes are crying ;((

  • @Anonymous user 096762 thank u. Is OK.

  • Version 46.5 works with Firefox ESR 52.5.3

    Download the file, drag it onto the addons screen, confirm install prompt

    Make sure you have disabled automatic updates for the addon (double click it at "Add-ons Manager" screen, scroll down, select "Off" for "Automatic Updates")

  • This is an awesome program that makes the unreadable font in fire fox readable. I would rate this app with 5 stars, since the author decided to be shady and add an expiration date i can only rate it at a TWO. Thanks to everyone who made a work around for this amazing app shame the author is shady though. I wish they would allowed us to continue enjoying this app.

  • @Hackodis
    I previously rated it at 5 stars; wish I could give it negative now.
    Mozilla ought to pull this.
    57 does not work with FF 57.
    56 no longer works with FF 56.
    Maybe a class action lawsuit by us folks with bad eyesight ...

    Anyone with a way to make the add on work in a Mac OS (10.11)? Everything posted here and elsewhere is Windows.

    Main thing I need is the bold.

    I'd gladly pay for an app or utility that does what 56 did - or pay Boris ...

  • It won't install for Thunderbird and there is where I need it.

  • Anonymous user cf029c - What version of Firefox are you using? I'm using 56.0. Your method doesn't work.

  • not working

  • Whatever you changed, it's still not working. No Icon can be found on Firefox nor Thunderbird to launch the App.

  • It just stopped working for firefox and thunderbird yesterday (Fri, Jan5). The text in the view is so smaller I cannot read it, especially in Thunderbird

  • Can't live without theme font size changer! Please fix it so that it works with FB and FF again! Thanks!