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install old version of thunderbird

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My Theme and Font Size Changer was no longer working on Firefox or Thunderbird (button was missing, etc.)....I believe from the Sept. 8th automatic update. I refuse to update Firefox past 42.0 because CoolPreviews is no longer supported on newer updates, but I've been updating Thunderbird regularly. To solve my problem, I downloaded an older version of Theme and Font Size Changer; it works great on Firefox--have all my fonts and colors and the button back--but it did not fix the problem in Thunderbird. https://addons.mozilla.org/en-US/firefox/addon/theme-font-size-changer/versions/

Where can i find older versions of Thunderbird--just back to August should be fine--as I'm hoping this may work.

Thank you.

My Theme and Font Size Changer was no longer working on Firefox or Thunderbird (button was missing, etc.)....I believe from the Sept. 8th automatic update. I refuse to update Firefox past 42.0 because CoolPreviews is no longer supported on newer updates, but I've been updating Thunderbird regularly. To solve my problem, I downloaded an older version of Theme and Font Size Changer; it works great on Firefox--have all my fonts and colors and the button back--but it did not fix the problem in Thunderbird. https://addons.mozilla.org/en-US/firefox/addon/theme-font-size-changer/versions/ Where can i find older versions of Thunderbird--just back to August should be fine--as I'm hoping this may work. Thank you.

Chosen solution

Hello. I did have the newest version of Theme and Font changer at first. My add-ons indicated that I had it, but in the end I went to the Mozilla thunderbird add-ons page and redownloaded it.

Works now. I am not going to ask why.

Thank you for responding. I also appreciate that you didn't assume I knew what to do once I got to the older versions page...thank you for listing the steps.

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All Replies (2)

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Theme and Font Size Changer 48.5 is the one to use for Thunderbird 45.3.0

The addon you are using for an older version of Firefox is not used by Thunderbird unless you have installed and added as addon extension into both Firefox and Thunderbird. So you could have an older addon extension used by Firefox and a more recent one installed into Thunderbird.

So I would first suggest you check the version you are currently using in Thunderbird and if it is not 48.5, then get it updated to see if all is then ok. It's not logical to go backwards in a Thunderbird version when there is already an addon which should be compatible.

If you do not want to try it and are happy to do back to earlier version: This is a link to older versions of Thunderbird.

  • Select which version you would like.
  • Select OS type. eg: win32 = Windows
  • Select language: eg: en-GB = English British
  • click on 'thunderbird setup xx.exe' to download.

If mac: 'thunderbird xx.dmg' If linux: 'thunderbird- xx.tar.bz2'

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Chosen Solution

Hello. I did have the newest version of Theme and Font changer at first. My add-ons indicated that I had it, but in the end I went to the Mozilla thunderbird add-ons page and redownloaded it.

Works now. I am not going to ask why.

Thank you for responding. I also appreciate that you didn't assume I knew what to do once I got to the older versions page...thank you for listing the steps.