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How do I reopen a closed window that got erased in Firefox?

so after the new firefox update all of my settings were changed back to default, and I often use alot of different windows and tabs and leave them open, and then some times close them to speed things up and so the computer does not crash or over heat do to running multiple windows at once, then if i need to find a tab from another window i closed, i will go into the history panel and reopen that closed window that contained the tab or set of tabs.

I had my firefox set so it would hold on to the last 10 or so closed windows, but after the update it got set back to default so it only saved the last 3, and last night (7/1/19) it erased one of my closed windows (i had 4 windows open and then closed one) after i closed another window and then that window took the place of it and the other was just erased. i looked around and could not find an answer to solve this issue. i found one question that was similar and they were told to use 

'jeffersonscher'

i used that with all of my different json files and json update files and all the tabs were and sessions were showing up but i could not find any of the tabs from that one window that was closed and erased 

is there a way to reopen or find that closed window that got erased?

so after the new firefox update all of my settings were changed back to default, and I often use alot of different windows and tabs and leave them open, and then some times close them to speed things up and so the computer does not crash or over heat do to running multiple windows at once, then if i need to find a tab from another window i closed, i will go into the history panel and reopen that closed window that contained the tab or set of tabs. I had my firefox set so it would hold on to the last 10 or so closed windows, but after the update it got set back to default so it only saved the last 3, and last night (7/1/19) it erased one of my closed windows (i had 4 windows open and then closed one) after i closed another window and then that window took the place of it and the other was just erased. i looked around and could not find an answer to solve this issue. i found one question that was similar and they were told to use 'jeffersonscher' i used that with all of my different json files and json update files and all the tabs were and sessions were showing up but i could not find any of the tabs from that one window that was closed and erased is there a way to reopen or find that closed window that got erased?

All Replies (11)

Hi foamrope, sorry to hear about this problem. It sound as though you have exhausted the most easily available files, so we need to consider more obscure options.

If the missing window wasn't in recovery.jsonlz4/recovery.baklz4, previous.jsonlz4, or the latest update file (probably from several weeks ago), then there must be a fairly small window of time where you had that window open?

Finding/Using Shadow Copies

You can use a utility program to search inside restore points to try to locate a recent file that's usable. (Please do NOT try to use the built-in Windows System Restore for this because you would lose too much data.) Here are the steps:

(1) Set Windows to show hidden files and folders:

https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files

(2) Download and run one of these two programs:

Within the most recent restore point shown in the program, you can explore along this path to see whether you can find a shadow copy of your profile:

\Users\your-user-name\AppData\Roaming\Mozilla\Firefox\Profiles\

(3) Two things to check:

(A) At the main level of the profile folder, check for sessionstore.jsonlz4 -- this file will only exist if the snapshot was taken while Firefox was closed.

(B) In the sessionstore-backups folder.

You can export interesting files to a convenient location such as your currently live desktop. Then you can use the Scrounger tool to view their contents.

Any luck?

If you lost personal data then it is possible that a new default-release profile folder has been created. See "Determine if Firefox has created a new profile":

You can open the about:profiles page via the location bar to check whether multiple profiles are present and what profile Firefox currently is using.

Firefox 67 and later can use a dedicated profile for each of the Firefox update channels and will lock the profile, so it can only be used by Firefox in a specific installation folder. For Release versions this profile would be a xxxxxxxx.default-release profile, profiles used in older Firefox versions usually used a xxxxxxxx.default profile (a refresh adds a time stamp).

i tried both of these and i still cant find that specific window :( i did find some other older windows but not the one i was looking for. what else could i try?

jscher2000 said

Hi foamrope, sorry to hear about this problem. It sound as though you have exhausted the most easily available files, so we need to consider more obscure options. If the missing window wasn't in recovery.jsonlz4/recovery.baklz4, previous.jsonlz4, or the latest update file (probably from several weeks ago), then there must be a fairly small window of time where you had that window open? Finding/Using Shadow Copies You can use a utility program to search inside restore points to try to locate a recent file that's usable. (Please do NOT try to use the built-in Windows System Restore for this because you would lose too much data.) Here are the steps: (1) Set Windows to show hidden files and folders: https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files (2) Download and run one of these two programs: Within the most recent restore point shown in the program, you can explore along this path to see whether you can find a shadow copy of your profile: \Users\your-user-name\AppData\Roaming\Mozilla\Firefox\Profiles\ (3) Two things to check: (A) At the main level of the profile folder, check for sessionstore.jsonlz4 -- this file will only exist if the snapshot was taken while Firefox was closed. (B) In the sessionstore-backups folder. You can export interesting files to a convenient location such as your currently live desktop. Then you can use the Scrounger tool to view their contents. Any luck?

i tried both of these and i still cant find that specific window :( i did find some other older windows but not the one i was looking for. what else could i try?

i thank the two people that replied but unfortunately the instructions from them were to no avail, i looked into my folder named 'jfzay9hf.default', which basically showed all of my firefox data and numerous folders of different data, in one of the replies it said to check the 'sessionstore-backups' folder to see if i could the previous session that contained the window i lost, but i could not find any from the date of the session i lost, i also tried to find a 'shadow copy' using a app called 'shadow explorer' to see if i could find a earlier version of the session..but i still found nothing. i looked around and found a folder named 'data reporting' and inside that was a archives folder. i found a something named '1561953795359.bceb0e3c-db98-4f51-b748-bf53f96491e3.main.jsonlz4' and the date for it was 7/1/19 and there was another with a similar name but a date of 7/2/19 which was around the time i lost that window and both of these files types were 'JSONLZ4'. i tried to view them with the jefferson scrounger tool, but they did not show any tabs or window/urls of any sort it just showed the name of the file i put in.

is there a way i can view these files to see what tabs/windows were on them with the scrounger tool? is there anything else i could do to try and get this erased window back, other than searching through my history for hours?

Shadow copies would be about the sessionstore.jsonlz4 file at the main level in the profile folder (xxxxxxxx.default in AppData\Roaming). This file is only there when Firefox is closed.

cor-el said

Shadow copies would be about the sessionstore.jsonlz4 file at the main level in the profile folder (xxxxxxxx.default in AppData\Roaming). This file is only there when Firefox is closed.

yes i already tried this and it did not solve the problem as i explained.

Note that you can use a user.js file in the profile folder to set a fixed value to the undo prefs.

user_pref("browser.sessionstore.max_windows_undo", 10);
user_pref("browser.sessionstore.max_tabs_undo", 25);

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

Note that user.js is read each time Firefox is started and initializes preferences to the value specified in this file, so preferences set via user.js can only be changed temporarily for the current session.

cor-el said

Note that you can use a user.js file in the profile folder to set a fixed value to the undo prefs. user_pref("browser.sessionstore.max_windows_undo", 10); user_pref("browser.sessionstore.max_tabs_undo", 25); You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page. Note that user.js is read each time Firefox is started and initializes preferences to the value specified in this file, so preferences set via user.js can only be changed temporarily for the current session.

i am sorry but how exactly would doing this help me find the window i lost? like i said i think i found the json files for the sessions/windows but i cant view them.

A user.js in the profile folder is helpful for future issues to prevent maximum undo windows from getting changed, unless a new profile would be created (an autoconfig file would work for all profiles).

If the scrounger utility didn't reveal the lost windows then you are likely out-of-luck. You would need a sessionstore file that has more than 3 windows to have a better chance.

foamrope said

i looked around and found a folder named 'data reporting' and inside that was a archives folder. i found a something named '1561953795359.bceb0e3c-db98-4f51-b748-bf53f96491e3.main.jsonlz4' and the date for it was 7/1/19 and there was another with a similar name but a date of 7/2/19 which was around the time i lost that window and both of these files types were 'JSONLZ4'. i tried to view them with the jefferson scrounger tool, but they did not show any tabs or window/urls of any sort it just showed the name of the file i put in.

The "datareporting" folder doesn't store session history.

You might try running your session history files through the older scrounger which uses a different method of mining URLs in case it can find anything else: https://www.jeffersonscher.com/ffu/scrounger_20180826.html