All Products Community Forum

Hi everyone,

I’ve noticed that Firefox tends to use a lot of memory when I run several browser-based tools at once — especially web calculators or dashboards that update data dynamically.

For example, when I’m testing a lightweight web calculation app (something similar to a gratuity calculator that updates values in real time), Firefox memory usage slowly increases, and sometimes the browser even freezes if multiple tabs are open.

I’ve already tried:

Clearing cache and disabling extensions

Running in Safe Mode

Using hardware acceleration on/off

Still, the problem persists.

So I’d like to ask:

1. Are there any specific settings or flags that can help manage memory usage better for interactive web tools?

2. Does Firefox handle JavaScript-heavy calculations differently compared to Chromium-based browsers?

3. Any recommended performance tweaks for developers testing such tools locally?

Would really appreciate advice from anyone who’s optimized Firefox for this kind of lightweight, web-app testing.

Thanks in advance! 🙏 bold text

Thunderbird is running (apparently properly) on both my (old) HP laptop, and on my (new) Samsung laptop. But the Thunderbird address book on the Samsung only shows the email addresses associated with emails that have been sent or received since I installed Thunderbird on the Samsung. It does not include the rest of my address book. Similarly, it only contains the emails that have been sent or received since I installed Thunderbird on the Samsung. When I follow the instructions to open the (Thunderbird) profile folder, I get a message that says “C:\Users\User\AppData\Roaming\Thunderbird\Profiles\fbclykvb.default-esr is unavailable.”

With help from Currys (where I had bought the Samsung), we were able to copy the (ApsData) Thunderbird folder from the (old) HP laptop to the (new) Samsung) laptop. (They also ran something called mailmerge, but I didn’t follow the precise details.) I can now find the Thuderbird folder in the AppData/Roaming folder. In the Profiles, there are 2 subfolders, hw7ms2fs.default-release and w1a31rjn.default. w1a31rjn.default has only one file – times.json hw7ms2fs.default-release has lots of subfolders and files, but no file named fbclykvb.default-esr. Thunderbird is still working properly on the Samsung, but I still can not access my larger address book, or emails that were receive or sent by Thunderbird on the HP. How do I fix it? The people at Currys tried to help, but they don’t know much about Thunderbird, and said I needed to get support from Mozilla.

Being in a rush after a botched TB update from v120 to 140.0esr, and missing disk backups, I reinstalled v102 and recreated two of my four email provider accounts in TB 102. Now. I'd like to try the update again this way: 1. export the few messages downloaded to the reinstalled v102 2. Completely delete v102 and any traces of TB on my C: disk (Program Files folder, user account folders, registry...) 3. Install the latest version (143 as I write this) 4. Copy and set as default (or import?) a two-weeks old disk backup of the old TB v102 profile into v143 without anything missing:

   - Four email accounts
   - All the messages in all the mailbox folders (received, sent, drafts, etc.) of these accounts
   - The complete archives folders structure and content
   - All the other folders I created as direct children of the email accounts in the TB "Folders" outline and their contents
   - one RSS feeds account and its settings
   - ~40 RSS feeds subscriptions and their settings

5. Import the recent messages from step 1 into the corresponding TB accounts.

Is that the correct way to do this?

I'm wondering about a few things:

   - Best email export format for later import?
   - Will the restored email accounts automagically reconnect to the provider accounts? I may have changed the format of one of them from Imap to pop3, and the server handled it very well, but it would be Imap again in TB after restoring the disk backup...
   - Why is v140 the only one with ESR in its name and not the following ones? I was on ESR when I froze 102 and blocked updates)
   - Is the Sqlite DB part ot the TB account file structure, and is it carried over when moving or duplicating that account?
   - Has the TB account folder and/or the Sqlite DB changed format between v102 and v143?

P.S. the email account for this post is among the inactive ones at the moment!

Hi

i use Mozilla at work, in logistics.

When booking shippments we use "nShift". Booking is repetitive, so the autofill function (in swedish its autofyll) is pretty useful, and we have used it extensively...now for some reason it has just disappeared and we cant get back.

See uppploaded imgage, tried to follow the instructions,..... also in my edition there is no subheading caled "Formulär & autofyll", it just says "Autofyll".

So the question is, what to do to get the autofill back.

Thnaks for all the help i can get.

///

!. link to youtube only flashes then plays only audio. Full video requires opening link in a new private browser window

2. Typing into search bar for Duck Duck Go in new tab page types directly into active bar...

3. Active bar is no longer at the top but is in Bookmarks toolbar...

I suspect some update problem.

Hello, I have spent the last couple of hours reading through other questions and posts but nothing seeemd to work. If I try to copy a shared link in OneDrive or SharePoint on my desktop and then paste that link into Outlook Web App, the paste function does not work. The option is there, but the actual pasting does not materialise. CTRL+V also does not work. The only thing that does work is if I paste the link into another window first and then copy again, and the CTRL+V works. Right click and paste never works. I have tried this in a private window and in safe mode. I have also checked the clipboard settings in about:config to make sure they are not working against me. It works fine on Chrome. I made a quick Loom to demo the issue: https://www.loom.com/share/911ae68d614947aa9ea6beaba0d2f5b0?sid=2257b601-939b-4d95-90d8-bb2c95b1ed81 Firefox is up to date, as is Windows. It has been like this since I moved over from Chrome a few weeks ago. Is this a common issue or a 'me' problem? I have seen all the workarounds, but I am trying to understand why right-click, paste just doesnt work. Any suggestions are much appreciated.

I am looking to archive old folders from mail addresses that I don't use anymore, but don't want to delete the folders. And once those are gone- I would like the rearrange the order of the folders. This second one seems like it should be easy but I am having trouble finding how to do that. Thank you

Dear all, After migrating Thunderbird to a new computer with Windows 11, I noticed that Thunderbird no longer opens links in emails. When I click on a link, no browser opens and nothing happens, even though I can see on the bottom bar that it recognises the HTTP link. How can I fix this? Reinstalling the programme did not help, and I would like to keep the profile and email settings I already have. Kind regards

I do not want to use Thunderbird anymore. So I deleted my two mail accounts, but thunderbird still remembers them - this I do not want. And how can I close thunderbird definitely, thunderbird also forgot already the main password... Thanks for help!

Dashlane not autofilling for a particular site - https://complete-deputy-report.service.gov.uk/login

Also, Dashlane DOES autofill cirrectly in latest versions of MS Edge & Chrome

Firefox 143.0.4 Dashlane App 6.2539.0 OS Windows 11 Pro v 25H2 Build(26200.6725)