How to download older version of Thunderbird?

I have an extension that I depend on and it is not compatible with the current version of Thunderbird so I need to backup until it starts working again. How can I downloa… (read more)

I have an extension that I depend on and it is not compatible with the current version of Thunderbird so I need to backup until it starts working again. How can I download earlier version of Thunderbird?

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Clear cookies and site data greyed out

For the last three days or so I have been haivng problems with loggin in to sites. I no longer log in automatically to my many of the sites I use, particularly those set… (read more)

For the last three days or so I have been haivng problems with loggin in to sites. I no longer log in automatically to my many of the sites I use, particularly those set for my home page such as IMDB.com, ebay, web.whatsapp.com etc. Everytime I restart firefox I have to log in again. This started I think wit hthe latest update 155.0.1 (my current version) installed 5th sept 26 or 155.0 installed 3 sept 26

It doesn't seem to be reading the cookies that exist. I have it configure so all cookies are cleared on exit except those in the exception list, which are those for my home page plus about 30 others I log into. There is definitely cookie data there for these sites. I hve tried everythinig but this clearly seems to be a bug. at the moment I am using Opera since the necessity to keep loggin in to every site every time is just too much.

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Thunderbird hangs due to POP3 server error right at the start. "An error occurred with the pop3 mail server. Unable to write to the mailbox""

Was on version 115, had this problem. Updated to version 155, same problem. One of the email accounts I set up on Thunderbird is redacted1@lake48.net, registered with 123… (read more)

Was on version 115, had this problem. Updated to version 155, same problem. One of the email accounts I set up on Thunderbird is redacted1@lake48.net, registered with 123-Reg. However, this is a forwarding address and has no email server, which is why I am getting the error now.

Messages addressed to redacted1@lake48.net are forwarded to redacted2@lake48.net, which does have a server, My system was to download from there and use a rule to divert the incoming message to my redacted1@lake48.net Inbox. This has worked OK until now. Thunderbird gives me this error right at the start and then does not respond, so I cannot get in to investigate account settings, and cannot access emails in other accounts such as gmail. 123-Reg has today changed its system, assuring me I don't need to change anything. Clearly I do, but I can't get in to change it.

What should I do to resolve this? I have no other access to my emails.

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VPN not appearing in Firefox for Android 154.0.1 August 2026

I'd like to try out the built-in VPN, but can't find it. I've seen many older posts about this, but nothing recent. It's now August of 2026. I'm using Firefox 154.0.1 on … (read more)

I'd like to try out the built-in VPN, but can't find it. I've seen many older posts about this, but nothing recent. It's now August of 2026.

I'm using Firefox 154.0.1 on Android 16. I'm in the United States.

I'm logged into my browser with my Firefox account. I know it's working as I can open browser tabs between my mobile device and other devices using my account.

I'm not seeing the built-in VPN feature.

"VPN" does not appear in Settings as described in https://support.mozilla.org/en-US/kb/mobile-android-vpn

By comparison, attached is a screenshot of what I have in Settings > Privacy and Security.

Any guidance?

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since the last update to firefox 155 the build in VPN is not working anymore

the build in VPN is not working anymore: the messages we get are often like "no internet connection". i did use it now for some weeks, but after the last update it stoppe… (read more)

the build in VPN is not working anymore: the messages we get are often like "no internet connection". i did use it now for some weeks, but after the last update it stopped working now for some days.

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Scrambled illegible letters in Firefox's interface

Hello! My Firefox browser is currently in a state where all fonts/letters in the Firefox interface (bookmark bar, settings, about page, website name...) are replaced by u… (read more)

Hello! My Firefox browser is currently in a state where all fonts/letters in the Firefox interface (bookmark bar, settings, about page, website name...) are replaced by undecipherable characters.

I've searched for similar problems already and tried so far the following steps to resolve, unsuccesfully...

  • Opening the browser in Safe Mode / Deactivating all extensions
  • Uninstalling and reinstalling Firefox

  • Disabling hardware acceleration
  • Trying on another profile




When I copy paste said text to another window (ex: Notepad, Chrome Browser…) it appears properly. And as you can see in the screenshots below the text in actual websites is readable -- only the browser's interface, setting, address bar... are scrambled.

Does that bug rings any bell? Do you have any other troubleshooting steps I should try to resolve this? Any help will be appreciated! : )

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Sending of the message failed. An error occurred while sending mail. The mail server responded: Sender address rejected: not owned by user Please check the message recipient "christine.krieger@a1.net" and try again.

Sending of the message failed. An error occurred while sending mail. The mail server responded: <anonymous@[10.0.0.31]>: Sender address rejected: not owned by user … (read more)

Sending of the message failed. An error occurred while sending mail. The mail server responded: <anonymous@[10.0.0.31]>: Sender address rejected: not owned by user a1.914306843. Please check the message recipient "christine.krieger@a1.net" and try again.

why do I get this on new download

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How to pin 1Password extension/icon on tool bar?

Had my laptop serviced at Best Buy, but upon booting it up the icon for 1Password in the upper tool bar was missing. Trying to figure out how to add it back. I use Mozill… (read more)

Had my laptop serviced at Best Buy, but upon booting it up the icon for 1Password in the upper tool bar was missing. Trying to figure out how to add it back. I use Mozilla Firefox and have Windows 11.

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New Emails going into a random folder instead of the Inbox

As of September 3, 2026 all my new emails are going into a random folder instead of the inbox. This is also happening on my wife's PC plus and we are not getting the emai… (read more)

As of September 3, 2026 all my new emails are going into a random folder instead of the inbox. This is also happening on my wife's PC plus and we are not getting the emails to our iPhones until we get out of Thunderbird. What has changed? This has not happened before.

Solved 3

Unable to write the email to the mailbox

I've been using Thunderbird on Windows 10 since last year sometime. Currently I'm on version 151.0.1. I've 4 x mailboxes here and since yesterday, 3 of them show me an un… (read more)

I've been using Thunderbird on Windows 10 since last year sometime. Currently I'm on version 151.0.1.

I've 4 x mailboxes here and since yesterday, 3 of them show me an unusual message when checking for emails. I tried attaching a screenshot but although the screenshot uploaded, I couldn't find a way to insert it here. But the message says Unable to write the email to the mailbox and asks me to check if I've write privileges (which I have) and to cheek the available disk space.(currently 101GB free).

The message is happening 2 or 3 times each day and lasts for about half an hour, then everything works fine again. Has anyone else seen this??

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Firefox became so Heavy

My hardware is low end from 2016, Pentium 3825U, HD Graphics, and 4gigs of RAM. In the old times, the browser was fast, but this year it has slowed down so bad. I needed … (read more)

My hardware is low end from 2016, Pentium 3825U, HD Graphics, and 4gigs of RAM. In the old times, the browser was fast, but this year it has slowed down so bad. I needed to switch to Thorium browser because Firefox became so heavy, using too much RAM and CPU. Please make the browser light, fast, and good for old systems again! (I want to use Firefox back)

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Font on certain sites is being forced to this weird one (NOT in private window though), font setting in accessibility does nothing to fix it

My font on some sites is being forced to this horrible condensed font and it's seemingly nothing to do with my font settings in browser. Thing is, I VAGUELY remember chan… (read more)

My font on some sites is being forced to this horrible condensed font and it's seemingly nothing to do with my font settings in browser. Thing is, I VAGUELY remember changing a setting SOMEWHERE to actually do this, but it's not the main font setting in accessibility. Furthermore this issue has only started happening in the last day or two and my vague memory of setting my font somewhere was years ago.

Is there any other setting in Firefox that affects default font for certain sites?

[Images attached from terraria.wiki.gg in a normal tab (with bad font) and private browsing tab (with the font it SHOULD have) for comparison]

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