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I believe with Update 154,0 my thunderbird has been freezing up. I can't see, to compress files or select some folders. After a few minutes everything freezes up. 21 AUGUST 2026

[redacted] @gmail.com

/edit: unlocked as other was made as duplicate.

I have Windows 11 operating system on my Laptop, but when I order merchandise online via Paypal, I get notification stating my device was recognized and was using Windows 10! I don't understand why this is happening. How do I fix this?

Try to get "tvlistingszap2it.com" --(which I have been using for 5 years)--- but it opens "newsnation" Started doing this on 17 Mar, 25. What is wrong ?? Can you fix it ??

please forgive me for asking again, but I REALLY need my addons to work. Firefox disabled my addons, forcing me to upgrade to a version of firefox that I don't need, since the old one was working just fine. The new version does not seem to appear to have downloaded properly, and neither version is allowing my addons to work or be re-installed. Please explain it to me like I am 5 years old, and help me to get this fixed without losing any of my info that might be stored in the addons.

 Thank you.

I've been using FF since release #3 and like it a lot since I cut my teeth using NetScape. The past few days FF will not open one of my email accounts. When I click on login, it brings up the logging on page and then just starts blinking and will not sign me on. If I use MS Edge to sign on it works fine. The email account has been working fine for many years so don't know what to do. I've deleted recent history, but that does not help. Any ideas will be appreciated as I like FF and don't like to have to use two different browsers to do my daily tasks. Thanks in advance for any help you can suggest. I'm currently using release 131.0.3 with W-10 on a desk top PC with DSL from my phone company with the email account with their ID. My phone company does no know about or support FF.

I installed Thunderbird (T-bird), and on the "Set Up Your Existing Email Address" tab, I entered my Xfinity e-mail address/password and clicked on "Continue". T-Bird is able to find the proper configuration in the Mozilla ISP database. I clicked the IMAP radio button and then "Done". That opens a popup window with the heading "Enter credentials for <my-email-address> on imap.comcast.net, but the window never prompts for anything (a prompt for my Xfinity password is what I expected). Instead I just get a message headlined "Unable to connect", with the subtitle "The connection was refused when attempting to contact localhost". This is followed by three suggestions for why that might be the case. I verified that: 1. The Xfinity site is NOT "temporarily unavailable" - I can log into Xfinity directly and see my messages. 2. My computer's network connection is operational since I can load any website at will. 3. I do have Windows firewall enabled, and I suspect that is root of the problem. How can I permit T-Bird to access the web??? Thanks.

Each time I start TB, I get this message: "The folder 'Inbox on redacted@aol.com' could not be compacted because writing to folder failed. Verify that you have enough disk space, and that you have write privileges to the file system, then try again." What does this mean and what can I do to fix it. Thanks. M. Campbell

Since recently 1~2 version, my Firefox keeps consume large amount of memory and release it repeatedly

Even I restart Firefox and do nothing, it will start doing this again

I use about:processes and about:memory to capture this seems the main process's "tab.query" causing this, please check

PS: sometime it will consume till system max (64GB) and cause my OS out of memory. PS2: that wave-like memory usage is cause by Firefox

I'm using the vertical tabs feature. I also tried enabling the "Expand sidebar on hover" option, which minimizes the side bar, and only expands it when you hover on it.

Issue: I have a lot of open tabs, and I'm usually working with the ones at the bottom of the list. When the bar minimizes the scroll position resets back to the beginning. So, every time I want to select a tab, I have to scroll back down, which makes this feature very hard to use.

Expected behavior: After the vertical bar minimizes, and I hover again, it should keep the scroll position.

During what I assume are high bitrate sections of YouTube videos (e.g. lots of movement, high resolution) YouTube will constantly drop frames.

Video for example: https://www.youtube.com/watch?v=KLuTLF3x9sA

I have tried: • Safe Mode • Installing the Flatpak and testing in that, which also has a fresh profile as I don't use the Flatpak version • Testing different related about:config settings – I can't remember them all now, but I tested every one I found googling that is related to the issue or hardware acceleration.

Hardware acceleration is for sure working. Turning it off makes the video drop to one or two FPS.

Chromium has no problem with the same video. However, you can see from the screenshots that both read the resolution/scaling of my screen differently, and it implies that Firefox is rendering something like 6314 x 3552 while Chromium is rendering at UHD, the resolution of the screen and my video. If I turn off all my Global Scaling, Firefox stops dropping frames (the same info box on YouTube states resolution is UHD), reinforcing my theory about scaling being the issue. Both are confirmed to be using native Wayland.

Thunderbird is not synchronizing with Mailfence. My other email accounts (Outlook, Gmail) work fine. TB connects to them, downloads message headers and displays the number of messages correctly. With Mailfence, the messages stop at "connected to imap.mailfence.com" and stalls there. The message disappears after a few seconds and nothing else happens. This happened this morning when I first launched TB. I then got an update to 128.11.1. No change. I did receive the Windows Update 2025-06 Cumulative Update sometime overnight prior to launching TB.

Am getting this message along with a recurring download of a specific email (keeps coming back even after deletion) that does not allow any other new messages to be downloaded. I do see new emails on my phone but will not read into Thunderbird??

Error: "Unable to write the email to the mailbox. Make sure the file system allows you write privileges, and you have enough disk space to copy the mailbox."

Tried: Troubleshooting, closing Thunberbird and reopening, rebooting windows system, compacting, etc. to no avail....

I have a HUGE problem with Firefox memory usage. Some open instances of firefox are taking anywhere from 600mb to 2.8gb of memory. Since firefox opens MANY instances even with only ONE active window, this very quickly uses all available memory (4gb) causing a full laptop crash.

More concerning is that CLOSING the worst instance of memory usage STILL leaves the single open page/tab open, so what exactly was the memory eating instance actually doing ???

I have included a screengrab of the many remaining instances of firefox in windows task manager AFTER closing the main culprit.

I have also included a screengrab of all the adblockers I use which I believed would limit unnecessary memory usage, but does not seem to be effective.

Many Thanks

Youtube just does not run well on the firefox browser, I have had this issue on my pc, as well as my laptop. Twitch, piracy streaming sites, 9anime all work fine this problem with loading and buffering is exclusive to youtube. I have tried resetting my firefox settings, changing the values for load times and resource usage in about:config and none of these have fixed my youtube.I have tried multiple fixes I've been recommenced by online forms. I have switched my user agent to make youtube think I am using chrome, I have disabled and removed all of my extensions including ublock origin, and loading youtube remains painfully slow. In fact, disabling adblock makes the load times even slower.

Also responding to my post with "hmmm durrr it works just fine for me" does not help anybody, stfu.

please forgive me for asking again, but I REALLY need my addons to work. Firefox disabled my addons, forcing me to upgrade to a version of firefox that I don't need, since the old one was working just fine. The new version does not seem to appear to have downloaded properly, and neither version is allowing my addons to work or be re-installed. Please explain it to me like I am 5 years old, and help me to get this fixed without losing any of my info that might be stored in the addons.

 Thank you.