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Problems with multiple session restores not working

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So I launch Firefox, open multiple windows, Firefox crashes because of too many windows. When I reopen Firefox, I get the option to restore the previous session, which opens all of the windows that I had previously opened. Great.

So I launch Firefox, open multiple windows, Firefox crashes because of too many window, I reopen Firefox, have the option to restore the previous session, open multiple windows instead, Firefox crashes, rinse and repeat. Firefox allows multiple levels of "session restore", allowing me to go back several iterations of crashes. Great. This is the ONLY reason why I switched to Firefox several years ago.

But, within the last 6 to 12 months something has changed. Now, I am only able to go back one level of crashes in "session restore" - the additional session(s) simply does not exist. I have Googled multiple times for a solution, but, the closest thing I have found is the "about:config" setting of "browser.sessionstore.max_resumed_crashes". The setting of "0" and "1" makes no difference.

I am currently using Firefox 43.0.4. Why does this functionality no longer work?

So I launch Firefox, open multiple windows, Firefox crashes because of too many windows. When I reopen Firefox, I get the option to restore the previous session, which opens all of the windows that I had previously opened. Great. So I launch Firefox, open multiple windows, Firefox crashes because of too many window, I reopen Firefox, have the option to restore the previous session, open multiple windows instead, Firefox crashes, rinse and repeat. Firefox allows multiple levels of "session restore", allowing me to go back several iterations of crashes. Great. This is the ONLY reason why I switched to Firefox several years ago. But, within the last 6 to 12 months something has changed. Now, I am only able to go back one level of crashes in "session restore" - the additional session(s) simply does not exist. I have Googled multiple times for a solution, but, the closest thing I have found is the "about:config" setting of "browser.sessionstore.max_resumed_crashes". The setting of "0" and "1" makes no difference. I am currently using Firefox 43.0.4. Why does this functionality no longer work?

All Replies (10)

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First, let's check out those crashes,

Some of your crash reports weren’t sent to the Mozilla Servers.

In the address bar, type about:crashes<enter>. Note: If any reports do not have BP in front of the numbers/letters, click it to submit them.

The crash report is several pages of data. We need the report numbers to see the whole report.

Using your mouse, mark the most resent 7 - 10 crash reports, and copy them. Now go to the reply box below and paste them in.

aboutcrashesFx29

Security Issue: Update your Flash Player Version 20.0.0.267
https://www.adobe.com/products/flashplayer/distribution3.html
Note: Windows users should download the ‘’’active_x’’’ for “Internet Explorer,” and the ‘’’plugin’’’ for “Plugin-based browsers” (like Firefox).

Note: Windows 8 and Windows 10 have built in flash players and Adobe will cause a conflict.

See if there are updates for your graphics drivers https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

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You may have corrupt sessionstore file(s).

Type about:support in the address bar and press enter.

Under the page logo on the left side you will see Application Basics. Under this find Profile Folder. To it’s right press the button Show Folder. This will open your file browser to the current Firefox profile. Now Close Firefox.

Locate the sessionstore file(s). Then rename or delete them. Restart Firefox.


Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac=Options)
key, and then starting Firefox. Is the problem still there?

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When I go to "about:crashes", it does not show any crashes since December 30, 2015. None of them have "BP" in front of them. Over the last six months or so, it shows an average of about 3-4 crashes per month, which is wrong.

Here is my general situation. I have Windows Task Scheduler launch anywhere from 15 to 30 tasks every day, mostly Firefox windows for sites that I want to visit, typically finishing by 9AM. At least 5 days a week, Firefox will crash before it has finished getting all of those window launched. Later in the day, sometimes I go back and manually launch a task to visit the site, sometimes i use Firefox's session restore to relaunch those windows. In the evenings, I might not close out all of those windows, so, the next morning Firefox would crash as more windows are opened. When I first started using Firefox several years ago, I was able to go back to embedded sessions at least 5 levels deep if not 10 or more. But, in the past 6 months or so, I can go back one level of session restore, but, although that level shows there is a window titled "Restore Session", that level is empty.

I have explored the "bad sessionrestore.js" approach several times, but, am not finding a corrupted file, numbered files, or, a corrupted directory. All of the help I find online are related to not having even one level of session restore. But, I haven't found any help about the second level not working.

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the_steve_randolph said

I have Windows Task Scheduler launch anywhere from 15 to 30 tasks every day

Not at the same time, I hope.

Disable all but the first 3 Firefox commands. Any problem? '

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No, they are all separated by at least 1 minute.

Once again, this is a situation where multiple levels of session restore used to work - now it doesn't. I did not change anything about Task Scheduler or Firefox (other than perhaps upgrading).

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Follow my last post. It could lead to the cause of the problem. Perhaps something about one of the manager entries is bad.

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Did you update Flash because Shockwave Flash 10.3 r183 that shows in the System Detail list is really too old?


Are you using an extension to handle sessions?

cor-el modificouno o

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FredMcD said

Follow my last post. It could lead to the cause of the problem. Perhaps something about one of the manager entries is bad.

Not sure what you mean here

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cor-el said

Did you update Flash because Shockwave Flash 10.3 r183 that shows in the System Detail list is really too old?

Are you using an extension to handle sessions?

After the problems with Firefox and Flash 11.3, I went back to Flash 10.3 as suggested by many sources. After so many problems with Firefox and Flash, I decided it wasn't worth the time to upgrade Flash.

So, with this version of Fsash having been in place for several years, how does it affect the change I have experienced in the past 6 months?

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So, I uninstalled Flash 10.3 then installed the newest version of Flash 20. Unfortunately this does not resolve the multi-level session restore problem. Also, I now have a few pages (but not Firefox) that crash when I didn't have that problem before.

Seems like Firefox has always had problems with Flash. I guess Mozilla is REALLY looking forward to HTML5 making Flash obsolete.