Try the Firefox version from the official Mozilla server if you currently use a version from the repositories of your Linux distribution.

https://www.mozilla.org/en-US/firefox/all/

Start Firefox in Safe Mode {web link}

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

my firefox version is good running bevor 3-4 weeks. I think not that version has problems. I'm not sure if the problem is coming after Version of firefox 73.

Whats the different of safe mode? I'm not using Add-Ons or only since years its deactivated.

https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode

Safe Mode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes). If the problem goes away, that tells us one thing. If it does not, that tells us something else.

Hi Nicolas, I don't know what that dialog is trying to tell you. Are you saying it blocks all the tabs in that window, not just that one tab?

Are you able to dismiss it using the Esc key?

If you close that window and then re-open it, does the dialog come back? To re-open it:

• "3-bar" menu button > Library > History > Recently Closed Windows
• "Library" toolbar button > History > Recently Closed Windows
• (menu bar) History > Recently Closed Windows

Firefox creates numerous session history files, but because session history is only for the immediately previous session, it is unfortunately too easy to lose it. Could you start by making a backup of your existing session history files? Here's how:

(1) To open your profile folder...

If Firefox is still running:

You can open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > "?" Help > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter/Return

In the first table on the page, click the "Open Directory" button.

(2) Copy out session history files

In your profile folder, double-click into the sessionstore-backups folder. Save all files here to a safe location.

(3) What files did you find?

The kinds of files you may find among your sessionstore files are:

• recovery.jsonlz4: the windows and tabs in your currently live Firefox session (or, if Firefox crashed at the last shutdown and is still closed, your last session)
• recovery.baklz4: a backup copy of recovery.jsonlz4
• previous.jsonlz4: the windows and tabs in your last Firefox session
• upgrade.jsonlz4-build_id: the windows and tabs in the Firefox session that was live at the time of your last update

To preview the contents of a file and save it as a page of clickable links, you can drag and drop it onto this page, then click Scrounge URLs:

https://www.jeffersonscher.com/ffu/scrounger.html

That tool is on my site, so please let me know if it doesn't work for you.

There are some session management extensions you could consider using to supplement the built-in feature. These are the ones I'm aware of that you might investigate/try out:

Use database storage:

• https://addons.mozilla.org/firefox/addon/tab-session-manager/
• https://addons.mozilla.org/firefox/addon/session-boss/

Use bookmark storage:

• https://addons.mozilla.org/firefox/addon/session-sync/
• https://addons.mozilla.org/firefox/addon/my-sessions/

Bookmark storage is more robust in that Firefox backs it up regularly. However, having the extra data show up when you are searching your bookmarks may be annoying.

Hi jscher2000. :-)

jscher2000 said

Hi Nicolas, I don't know what that dialog is trying to tell you. Are you saying it blocks all the tabs in that window, not just that one tab? Are you able to dismiss it using the Esc key?

I open Firefox then it loads any Windows and Tabs after this coming this message without text. ESC doen't make anything. I must click x to close the message-box after click "x" its stop load windows and tabs. I can use only opened Windows. The strange thing is thats not a specially site does make problems. After close Windows with "x" i close firefox process and do reopen all Windows and that I do 4-5 and after 5 trys all windows and tabs are open.

jscher2000 said

If you close that window and then re-open it, does the dialog come back? To re-open it:

• "3-bar" menu button > Library > History > Recently Closed Windows
• "Library" toolbar button > History > Recently Closed Windows
• (menu bar) History > Recently Closed Windows

Also no, when the message error is coming without text an i close it and try to open latest window, the window without text isn't coming.

jscher2000 said

Firefox creates numerous session history files, but because session history is only for the immediately previous session, it is unfortunately too easy to lose it. Could you start by making a backup of your existing session history files? Here's how: (1) To open your profile folder... If Firefox is still running: You can open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > "?" Help > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter/Return

In the first table on the page, click the "Open Directory" button. (2) Copy out session history files In your profile folder, double-click into the sessionstore-backups folder. Save all files here to a safe location. (3) What files did you find? The kinds of files you may find among your sessionstore files are:

• recovery.jsonlz4: the windows and tabs in your currently live Firefox session (or, if Firefox crashed at the last shutdown and is still closed, your last session)
• recovery.baklz4: a backup copy of recovery.jsonlz4
• previous.jsonlz4: the windows and tabs in your last Firefox session
• upgrade.jsonlz4-build_id: the windows and tabs in the Firefox session that was live at the time of your last update

To preview the contents of a file and save it as a page of clickable links, you can drag and drop it onto this page, then click Scrounge URLs: https://www.jeffersonscher.com/ffu/scrounger.html That tool is on my site, so please let me know if it doesn't work for you.

---

There are some session management extensions you could consider using to supplement the built-in feature. These are the ones I'm aware of that you might investigate/try out:

Use database storage:

• https://addons.mozilla.org/firefox/addon/tab-session-manager/
• https://addons.mozilla.org/firefox/addon/session-boss/

Use bookmark storage:

• https://addons.mozilla.org/firefox/addon/session-sync/
• https://addons.mozilla.org/firefox/addon/my-sessions/

Bookmark storage is more robust in that Firefox backs it up regularly. However, having the extra data show up when you are searching your bookmarks may be annoying.

Thank you for explications of Backupfiles in sessionstore folder! Thanks i have installed the extention to save all my open tabs.

Just FYI -

Are you familiar with:

camp-firefox.de https://www.camp-firefox.de/

RobertJ said

Just FYI - Are you familiar with: camp-firefox.de https://www.camp-firefox.de/

You will be say this is help in german language? Yes, when i find help. Its official help?

camp-firefox does not appear to be an "official" Mozilla forum. I was simply offering that you could post on both forums.