Separate Issue: Update your Flash Player Note: Windows users should download the ActiveX 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. Install the plugin only. Not the ActiveX.

Flash Player Version: Version 26.0.0.151

https://get.adobe.com/flashplayer/ Direct link scans current system and browser Note: Other software is offered in the download. <Windows Only>

https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, Win IE . . . .) Note: Other software is offered in the download. <Windows Only> +++++++++++++++++++ See if there are updates for your graphics drivers https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration

Firefox v55 has been having problems with the bookmarks/history file.

I called for more help.

Look on your desktop. Do you see a folder called; Old Firefox?

https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

Type about:profiles<enter> in the address bar. How many profiles are listed? How many should be there?

Thanks, but there is no "Old Firefox", and I only have one profile: "Profile: default This is the profile in use and it cannot be deleted." I'm hoping for more hints...

https://addons.mozilla.org/en-US/firefox/addon/places-maintenance/ Places Maintenance Allows to run Maintenance tasks on the database that drives Places, the bookmarks and history module behind Firefox.

Open the Add-ons Manager. Locate the add-on and press the Options button. Then press Next on the bottom.

Thanks, I installed "Places Maintenance", what do you suggest to do next? Thanks in advance for any further help1

Did you run it?

Thanks for bearing with me! Actually, I cannot really find out how to run it, not even https://support.mozilla.org/en-US/questions/1045712 seems to help. Ultimately, however, via about:support I found: "Places Database Integrity", however: > Task: checkIntegrity - Unable to check database integrity > Task: checkCoherence - The task queue was cleared by an error in another task. > Task: expire - The task queue was cleared by an error in another task. > Task: vacuum - The task queue was cleared by an error in another task. > Task: stats - The task queue was cleared by an error in another task. > Task: _refreshUI - The task queue was cleared by an error in another task.

Try disabling graphics hardware acceleration in Firefox. Since this feature was added to Firefox it has gradually improved but there are still a few glitches.

You will need to restart Firefox for this to take effect so save all work first (e.g., mail you are composing, online documents you're editing, etc.,) and then perform these steps:

In Firefox 54 and below:

1. Click the menu button and select Options (Windows) or Preferences (Mac, Linux).
2. Select the Advanced panel and the General tab.
3. Uncheck Use hardware acceleration when available.
4. Close Firefox completely and then restart Firefox to see if the problem persists.

In Firefox 55 and above:

1. Click the menu button and select Options (Windows) or Preferences (Mac, Linux).
2. Select the General panel.
3. Under Performance, uncheck Use recommended performance settings. Additional settings will be displayed.

   

4. Uncheck Use hardware acceleration when available.
5. Close Firefox completely and then restart Firefox to see if the problem persists.

Did this fix your problems? Please report back to us!

If the problem is resolved, you should check for updates for your graphics driver by following the steps mentioned in these Knowledge base articles:

• Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

• Upgrade your graphics drivers to use hardware acceleration and WebGL

Thank you.

Try to disable multi-process tabs in Firefox. You can disable multi-process tabs in Firefox by setting the related prefs to false on the about:config page.

browser.tabs.remote.autostart = false browser.tabs.remote.autostart.2 = false

http://www.ghacks.net/2016/07/22/multi-process-firefox/

Type about:config<enter> in the address bar. If a warning screen comes up, press the Be Careful button. At the top of the screen is a search bar.

Thanks. I followed both recommendations, but the History Library is still empty upon restart. When I go to History-Library->Restore->...Sept..11.... 641 Items, I get the message "This will replace all of your current bookmarks with the backup. Are you sure?", but it's not about *bookmarks*, I don't want to touch them: they are OK. Please help, thx for your patience.

P.S. I also still get "> Task: checkIntegrity - Unable to check database integrity"

It means something is wrong somewhere.

Follow these instructions;

Type about:support<enter> in the address bar.

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

This is your current profile. Copy the folder As Is to a folder on a thumb drive or another folder on the hard drive.

This will be your backup if anything goes wrong...

Note: v55 has been giving users problems. Reinstall v54.

https://support.mozilla.org/en-US/kb/install-older-version-of-firefox?cache=no Be sure to read everything here.

If you still want to downgrade, look under; I still want to downgrade. Click the Directory of other versions and languages link. Look for the directory of the version that you want. But, remember that old versions may have security issues.

You should also check out Firefox; Extended Support Release {web link} ESR Notes System Requirements

1) I'm not sure whether I'd like to run into security issues by downgrading. Is there a good chance that the next upgrade resolves the issue? 2) Can I find out whether past history was lost, or whether it's just hidden/inaccessible? Is the past history still there by means of "History-Library->Restore" (see yesterday's post), or is it lost forever? Why does the dialog there mention "bookmarks"?? Can I save the current bookmarks, run a Restore, get back the past history this way, and then maybe update the bookmarks from the ones I saved? Thanks a lot in advance!

Downgrading to v54 will have no security issues for now. Plus it may bring your data back.

If the Places Maintenance extension can't repair the places.sqlite database then remove all places.sqlite file(s) in the Firefox profile folder to make Firefox rebuild the places.sqlite database from the most recent JSON backup in the bookmarkbackups folder.

• keep a backup copy of places.sqlite in case a new places.sqlite database has to be created
• http://kb.mozillazine.org/Unable_to_process_the_backup_file_-_Firefox

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.

• Help -> Troubleshooting Information -> Profile Directory:
  Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder
• http://kb.mozillazine.org/Profile_folder_-_Firefox

Sorry for the delay, but I've been terribly busy. And I'm also sorry for the followup-questions. I'm very grateful for all your help! @cor-el: After exiting and removing the files places.sqlite (30M), places.sqlite-wal (4.9M) and places.sqlite-shm (32K), restarting firefox I only got places.sqlite (5M), I'm afraid? @FredMcD: Is there no way to find out whether places.sqlite is maintained while browsing? It wouldn't be such a big problem if the history is temporarily lost, as long as it comes back with the next upgrade or so?

gf__ said

It wouldn't be such a big problem if the history is temporarily lost, as long as it comes back with the next upgrade or so?

History is stored in the same file as your bookmarks. If the file is lost, only your bookmarks can be restored thru backups.

Have you tried reinstalling v54?