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Firefox Windows "Vanish" & Re-appear on Restart

  • 26 replies
  • 3 have this problem
  • Last reply by John99

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This is a continuation of the problem report (with the exact same question) that had no solutions and was recently closed. I have no idea why an active problem report was closed. This is actually the THIRD instance of this problem report.

I had another4 occurrence a few minutes ago. I installed three MS Windows 7 patches, and a reboot was required. After the reboot, Firefox started with only 10 windows - my main window was missing. I ran my script to archive and process the three files - previous.js, recovery.bat, and recovery.js . Then I exited Firefox and re-started it. On restart, all 11 windows were present. I still do not have an answer to these questions :

1) WHY does this occur?

2) When it does occur, WHAT DIAGNOSTICS can I run to help debug this problem? This is clearly a bug in Firefox, and I want it fixed. I assume that I am the only one who is experiencing this problem, and I am willing to do almost anything to help debug this problem when it next occurs.

For those who have not read the other two problem threads - I am always running the latest non-beta Firefox, and I always run with add-ons disabled. This is a Windows 7 Professional 32-bit system.

--Barry Finkel

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bsfinkel said

Here is a partial reply ....
2) If I shutdown cleanly, then sesssionstore.js will be used at re-start. If I am missing one or more windows and I do a clean "Exit", then the sessionstore.js file should reflect the state of FF before the clean "Exit. Either it reflects only the displayed windows or all the windows, even those that somehow are not displayed. I do not understand how FF can be missing one or more windows, then I do a clean "Exit" and restart, find windows still missing,, then do another clean "Exit" and restart, and then find all windows present. I am currently looking at my scripts that process the .js files to see if they are correct in their counts of "tabs" occurrences. I will post more tomorrow after I do more research.

Conjecture but given your hangs, oom & other crashes and startup issues I wonder if, and how frequently Firefox is in fact exiting and starting up cleanly, and whether it is falling back on other copies of sessionstore files rather than using the expected ones.

If you are concerned about troubleshooting the multiple issues or filing one or more bugs, you probably need to study this in a more controlled fashion and not by trying to do so with the only profile that has important open tabs in it.

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Barry, I have added an escalate tag. Possibly Helpdesk or someone else will chip in. (Anyone new to this thread please also see #answer-892596 link and note the user has multiple issues with the current Firefox & Profile)

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Here is an update. i looked at my awk script (that processes the .js files so that they have line feeds at appropriate places), and I found a debug statement that was causing the script to terminate early. I re-ran the script against my 125 saved .js files. I then made a table of all of my Firefox tabs and in which.js files they do not appear.

My interpretation of the way FF starts is this: if there is a sessionstore.js file (from a clean FF exit), then that file is used to produce the windows and tabs on restart. If that file is missing, then one of the three files in the sessionstore-backups sub-directory is used. My scripts captured the files in the sessionstore-backups directory; it was not until about a week ago that I captured also the sessionstore.js file, if it exists.

In my summary table, I did not find any .js file that had a window missing. Where the window did not exist, it was either because I had not yet created that window or I had closed that window. On 08/06/2015 I had multiple restarts of FF due to missing windows, and somehow one of my windows disappeared. But it was a window for a project that I had finished, so the window loss is not important. I do not know which restart that day caused the window to vanish, but that is unimportant.

I assume that the only way FF knows if it is restarting after a crash is the absence of a sessionstore.js file. I also assume that there is no other test in the code during a start-up. This leads me to believe that the sessionstore.js file or one of the backup .js files is the ONLY file that determines what windows and tabs start during FF initialization. My saved files show no missing windows, and if there had been a missing window, I noticed it, Exited, and then restarted FF, then that missing window would have had the window missing, and any restart would not have that window. This has not been the case. The .js file that has been used when I notice a window missing is, indeed, INTACT. It is not these .js files that are causing the windows to vanish.

I made a log of FF restarts where there have been missing windows, and many have been after FF has crashed,. But some have occurred after a clean shutdown of FF.

I also have stopped logging which restarts display the "Embarrassing" window. I have no idea what the appearance of that start-up window signifies. The window states that there is some error in one of my windows/tabs. I have no idea what the error might be, as I always tell FF to re-start with the old configuration, and FF starts (albeit on some occasions with a missing window). Not all restarts display the "Embarrassing" message.

--Barry Finkel

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I had a curious recurrence yesterday. FF was beginning to misbehave (see my other trouble ticket)_ so I decided to Exit FF. Just before I did, I got an e-mail that said that Adobe had issued a new version of Flash. So, I began installing the new Flash on FF. This is the first time that the Flash installation REQUIRED me to shutdown FF during the installation. In the past, after the installation, Flash would tell me to restart the browser, and a test of Flash without a restart would show me that the new version had been installed. (Flash on IE11 always requires a restart of IE to get the new flash visible.) When Flash wanted me to Exit FF, I did that. It took about three minutes for FF to terminate, but it appeared to terminate cleanly. Then I let the installation of Flash to complete. As the Flash installation always opens a new Adobe window with an ad for another Adobe product I might want, i did not click the "Finish" button on the Flash install. I did not want this ad window to start before I had restarted FF. Instead I looked at the saved FF recovery files. STRANGELY, there was no sessionstore.js file; I have no idea shy. I saved and processed the other three files. When I started FF, two windows were missing, so I did an Exit. I saved the sessionstore.js file (which now WAS present). and then restarted FF. FF started with all the windows. I looked at the newly saved files, and all had all of my windows.

--Barry Finkel

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I am posting an IMPORTANT update here, as I cannot get to the last posting to post my reply there. I am posting this using IE11. I installed FF 48.0 Friday afternoon (08/05), and after FF takes over 15 minutes to load my 12 windows, it becomes non-responsive and crashes within one hour. I tried re-installing 47.0.1 (via 48Firefox Setup Stub), but that installed 48.0 IS THERE A WAY I CAN RE-INSTALL 47.0.1? The latest star. t of FF lasted 19 minutes before it crashed.

Here are the recent (48.0) crashes:

08/05/2016 04:50 PM 51 bp-378341ef-3e85-4495-a5c0-1b4ca2160805.txt 08/05/2016 05:27 PM 51 bp-1701bce8-53c3-4f61-9767-1a0e92160805.txt 08/07/2016 01:45 PM 51 bp-e26a4a2a-4b4e-4dd1-ba1e-2deb92160807.txt 08/07/2016 02:37 PM 51 bp-a28b4a60-1a30-406d-ab62-3454f2160807.txt 08/07/2016 03:46 PM 51 bp-16dd31fd-e3ff-4bf5-8cd2-939a82160807.txt 08/07/2016 08:49 PM 51 bp-a0fc6b75-1793-48df-bcac-bb9202160808.txt 08/07/2016 09:54 PM 51 bp-54bdeaf3-6cae-4835-ae9c-daf382160808.txt 08/08/2016 11:01 AM 51 bp-78522fbc-d7b4-4764-847b-69c742160808.txt 08/08/2016 11:26 AM 51 bp-c1d3e64d-ef89-4fd3-9037-d18462160808.txt

These data are from the \Crash Reports\Submitted subdirectory; obviously I cannot use "about:crashes" to look at any of these.

--Barry Finkel

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If you wish to try Fx 47 then use the Fx47 installer not the Fx48 stub.

You could of course try a new Firefox profile and may well find it then runs ok. I glanced at a few of your Crash Reports from your last post and they showed Firefox used more than 90% of available memory. That is probably excessive enough to expect a crash.


Whilst Firefox is able to run a profile it is relativly trivial to split the Windows for different projects in to separate profiles. That could become near enough impossible once the profile has degraded to the point of being unusable, Or rather I should say I do not understand how to correctly edit the sessionbstore files to do that.

At least you may have an option to go back to a previous working session store. it would be worth backing up your profile (I have not re read your threads, but you probably already back up profiles.)

I am posting an IMPORTANT update here, as I cannot get to the last posting to post my reply there. I am posting this using IE11

I am not entirely sure I understand the comment about not being able to get to your post. Maybe it is because your bookmarks are not available. This is a search for your questions link if it helps

Does Firefox work in a new profile ?


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