Firefox Community Forum

Hi. Yesterday something weird and unexpected happened to my Firefox and amongst other things it lost all my open tabs, of which there was about 70 or so. Another strange thing which happened is a website I use turned into Japanese language all on its own and in the end I was forced to delete cookies for that website to revert it to English, even though it was never changed in the first place. My homepage shortcut tiles were also all rearranged and some deleted. I have no idea what caused all this, but the biggest issue for me is that I lost all my open tabs. I refreshed Firefox to try to cleanse whatever it was that caused this, but even before this I lost my tabs.

My question here is; I am sure that the history of those open tabs is still listed somewhere on a file and I can get back my previous session which had all the tabs on it, but I have no idea where it is or where to look. How do I do this and where do I find the older file with the open tabs.

Thanks.

Why won't Firefox open any new windows? I give ir the command to open a window and yet all i get are tabs and I never click on open a tab. I have an HP probook this for windows 10 and i am also having the same problem with Chrome. I have uninstalled and reinstalled chrome and that did not fix it so it is not that. What would cause this? I have already cleared the cache cookies history browsing etc. and nothing is fixing it. PLEASE HELP.

Hi.

This message has three sections: little background, little rant, and little help from my friends.

Little background: I use PCs since Commodore 64, and internet since dial-up modems. Apart for some curiosity attempts with other browsers, I always used Firefox. Back then you either could do some DIY or you were done for. So, I am not a noob. And yet I am not a programmer, and do not have to damn be in order to use a damn internet browser. I have no words to express how negatively the choice of changing the behavior of the X button, to make it disappear when a certain amount of tabs are open, affects my user experience with Firefox. I tolerated it version after version. Found mentions of about:config tweaks which never worked. Found mentions to css codes which seemed so complicated that I just gave up (I also don't have much capacity for such things atm). I was ready to get rid of Firefox today after all this time of being loyal. I would have, if it was not for Cor-El. (Cor-El you can put this testimonial on your website if you'll ever start a consulting business).

Little rant: I SO SO SO SO SO SO MUCH HATE bad UX Design! And the FIRST definition of bad UX Design is when a designer imposes their own tastes and preferences on the users, or makes assumptions (based on their own usage) about how users would do things. I don't give the lesser s... if Firefox's UX Designers usually only have few tabs open, or don't mind clicking on a tab to make the damn X button appear, or would gladly abandon their beloved ergonomic mouse to buy a standard one with a mid button just to close tabs, of whatever the f... was going on in their minds when they decided to remove such an ESSENTIAL FEATURE!!! This change is WRONG! Nobody asked for it, nobody wants it, nobody likes it. The X button was not disturbing anybody. WHY must we tweak some f... about:config setting or ask in this Community for some css code to get back what should have never been removed!!!??? DO YOUR JOB, which is to make OUR user experience better, OUR, not yours!!!

Little help from my friends: After quick searches over a long time where I couldn't dedicate more resources to this, I came here determined to dig deep to find a solution. And I've found a few posts with answers from Cor-El. I followed his instructions in THIS post to configure a css file with the code that he provided in THIS other post (because I thought I didn't want the delay offered by the code he provided in the former post). Problem solved.

Now a question for Cor-El: Is it just me or the solution with the two browser.tabs settings does not work? It's the first thing I tried. I went from 50/50 to 200/200 to see if size matters. But no chance. Maybe there is another setting that must be activated for these to have effect? Or was their effect on the X button removed in newer Firefox versions (like the UX Destroyers really hate us)? Btw, I wanted to see how the delay thing would work, so I tried the code you gave in the first post, and it didn't have any effect. Whereas the code you modified for a guy in THIS post works perfectly. What could be the reason?

And 2 requests: - can you make some guide or pinned post about this, where you put together the info you gave in different posts? Something with your super easy instructions how to create a css file, and the two codes (with and without delay). And if the browser.tabs solution can still work, that too. All info in one single place, easy to find. - can you point me to a (possibly ADHS friendly) resource to more css codes for other useful tweaks, and to an explanation of what all about:config settings do? I like to tweak things to my needs. But I get overwhelmed if I have to read through tons of material. Thanks :)

Bonus Material, Little Rant part 2: It's good and nice that people help each other and I am thankful, but it does not need to come to this. Sure, I've read that the (ridiculous) reason behind the choice of making the X button disappear was to avoid accidental closure of tabs. But WHY taking for granted that we are some !diots who can't even use a mouse properly? And even if it happens once, we can still go to the damn "recently closed tabs"! But no, they had to remove the X button for all of us, to prevent a bunch of !%#@! from maybe sometime accidentally closing a tab. Why not just adding an option in the settings (NOT in some hidden "about:config") to let us choose if we want to have the damn button or not? Btw, a lot of these about:config tweaks are really useful and not dangerous at all and should imo be included in the normal settings. Keeping things simple and tidy does NOT mean reducing options. Unless you're Apple.

Please God-zilla let these [censored content] UX Designers read this post.

Amen and happy new Xear.

In early June 2025 I finally ditched Windows 10 for 11 and I've been a Firefox user since practically the very beginning of Mozilla.

Now, I notice that the "Restore Previous Session" button in the drop-down of the FF menu is missing. Additionally, I discovered late in the game that Mozilla DID listen to me and gave us the ability to "name" or "tag" an entire window in the browser. This was a HUGE boon to productivity as I'm constantly toggling from window to window to tab to tab.... Now, with the most recent update this ability seems to have disappeared....

Hello, sadly I have the problem since a few days that firefox opens a new tab with the same error every time I google something or click on a new page/subpage etc. The URL on the error page is all the time "https://0.0.0.1/" mentention of course a page loading error. I don't know why firefox keeps oppening new tabs with this URL. I allrady tried to use the clearing function and even reinstalled the software, nothing worked. Maybe somebody can help me solving this problem, it is very annoying to have multiple new error-tabs per minute in a normal work flow. Thanks and best regards, Thomas

With multiple tabs open, the "X" close button disappears; in Safari, the "X" appears on hovering, not in FF, so I have to open the tab to close it. It's an annoyance

Sometimes drag functionality stops working. I can't grab a tab to move it to another position or to a new window. (Holding left click on the tab and moving the cursor does nothing). Also, re-merging the tab with another firefox window stops working. (Dragging a tab to a firefox window from another firefox window doesn't merge them. It does nothing) I can right click on the tab and select Move to move it to a new window but dragging stops working. I have to close Firefox and start it again (sometimes twice), then dragging starts working again. This happens multiple times a day. I am on Linux Mint and the version is 126.0 (64-bit). This problematic behavior has only recently began.

PROSZĘ zróbcie czułość rozwijania bocznego panelu. Nie wiem czy to tylko w ostatnim czasie ale bardzo ciężko najechać na coś kursorem blisko bocznego panelu ponieważ ten odrazu się rozwija. Jestem zadowolony z tej formy kart przeglądarek więc chciałbym przy niej pozostać, natomiast ta czułość rozwijania kiedy kursor myszki jest stosunkowo daleko jest irytująca i znacząco utrudnia korzystanie z przeglądarki.

Hello, I used to have Microsoft Teams as a pinned tab (in fact I think it was my first pinned tab), which I no longer need as I now have the Teams app on my computer. I have tried unpinning the Teams tab but whenever I close & reopen Firefox, it reappears - it doesn't show up initially, but will pop up 5-10 seconds after Firefox starts (my other pinned tabs show up straight away) - so I have to close it each time. Not a big issue I know but kinda annoying - any suggestions/solutions?

This is the procedure I followed:

Close firefox

Copy previous.jsonlz4 file to the main level in the profile

It has all the tabs i used to have in it because I made a backup a few days ago

Rename the file to sessionstore.jsonlz4

restart firefox

I get the same single tab I had before i did this

when i go to history tabs, all that is there is the single tab i currently have

Appreciate your help/gary

Yesterday I had an event in which, due to some combination of computer glitch and user error, my Firefox window was closed and then Firefox was shut down in a two-step process. This left me with a sessionstore.jsonlz4 file consisting of no open tabs but with an enormous closed window full of tabs. I've used this utility to verify the contents of my sessionstore file.

I know how to rescue a previous session's tabs according to these instructions. I've done it many times. However, this time I'm finding that the only way to access Recently Closed Windows seems to be to first Restore Previous Session, and the only way to Restore Previous Session seems to be to have at least one tab in the sessionstore file that is not in a closed window. Therefore, I cannot access the tabs in my sessionstore file.

The best solution I can think of would be to edit my sessionstore file so that it contains at least one tab that is not closed. This would allow me to Restore Previous Session, and then find the tabs I want under Recently Closed Windows. However, I do not know how to edit a sessionstore file.

Specs: MacOS Monterey 12.6.9 Firefox 121.0

Last October my sessions were gone after a Firefox Update. I asked for help here: https://support.mozilla.org/sv/questions/1394685 and eventually got kind help from @cor-el (that unfortunately wasn't skilled enough to understand) and from @RayGibson57. But by then, my life was in a flurry and I didn't have time to try the advice. And so, after a while I had, with some effort, gathered many of the old tabs back again, and built up new sessions.

This Monday I was trying to internet while having high fever (something people should never do :o ). I left three blank windows open when I shut down the computer, and next morning those three were the only ones Firefox wanted to remember.

(I still find this change frustrating, bordering on infuriating: what happened to "Choose how many old sessions you want Firefox to remember", I think the maximum was ten?)

Now the fevers left and I went to those answers to try. That Q/A was archived though, so I'm starting again here, from as far as I got following King Rays instructions. They were:

1. Open the application menu (3 horizontal lines) next to the address bar.
2. Click on Help -> More troubleshooting information.
3. With that page open, find Profile Folder and click on Open Folder. That's how you get to the folder with backup files in it.
4. Set computer up to see all the extensions & system files. By default, the extensions don't show up (.jsonlz4 is an extension).
5. I found an older file in that sessionstore-backups folder and copied it one level back to the main profile folder.
6. Renamed the sessionstore.jsonlz4 to sessionstore.jsonlz4.old and the file I copied, I renamed to sessionstore.jsonlz4.
7. Opened Firefox and that missing window was in the history so I could open it.
8. Don't make any typos here, because Firefox won't find the files it needs to open.

I got as far as finding the Profile folder and the sessionstore-backups folder.

But I cant find any jsonlz4 file called "sessionstore". Only a "sessionsCheckpoints" and that one is a json file, and the date modified is today.

See screenshots please!

Can anyone talk me trough this like Im a grandmother from Sweden with extremely limited coding & tech skills (which is what I am)?

Up until Firefox 116, Reopen Closed Tab (Ctrl+Shift+T) would reopen closed tabs, and Reopen Closed Window (Ctrl+Shift+N) would reopen closed windows. There was a clear bifurcation, so I could freely close windows and not worry about it polluting my tab history in another window.

The latest change has thrown out that advantage, and now Reopen Closed Tab reopens both tabs and windows, while Reopen Closed Window still just reopens windows. This makes the later essentially useless and the former much more difficult to use for me.

I assume this was done to just continue copying Chrome in all respects since that's how it handles it, but the changelog just vaguely states, "This change is in anticipation of upcoming changes to recently closed tabs."

Does anyone know if there's a setting to separate the two functions again?

Help, I do not know how I got stuck with this but every time I go to twitter I get this tab pop up window and cannot get rid of it. I am not versed enough to get rid of it. Please, please help get rid of it. https://twitter-com.translate.goog/home?_x_tr_sl=en&_x_tr_tl=en&_x_tr_hl=en-US

So I enabled push notifications for Google Calendar. Every time there's a notification, Google Calendar ask if I want to enable "Switch to this tab" for their notifications. I accidentally turned it on, then I managed to turn it off. Except it now keep asking me if I want to enable it.

Looking at the settings, the only two options available are "Always ask" and "Yes", with no way of just saying no... why?

Hi,

I have the following problem: Windows 7 crashed after coming back from standby. When I restarted Firefox it restored a 3-month-old session. The sessionstore.jsonlz4 file was missing in the profile folder. I searched for a backup in the sessionstore-backups folder; unfortunately all were too old. Windows Restore was not running on my computer.

Using EaseUS Data Recovery I found a recovery.baklz4 file from 10 days ago, tried renaming it etc. but Firefox won't use it for recovering. It is probably corrupt ...

I used https://www.jeffersonscher.com/ffu/scrounger.html but I get an error saying: Session history file contents could not be read?

Is there any way to repair the file or extract the URLs to use them manually?

Or any other solution is very welcome! Thank you very much!