Profile data can be removed or not recorded in several ways;

• 1) Running Firefox in Private Mode (nothing is recorded)
• 2) Privacy settings; (In the address box, type about:preferences#privacy<enter> in the address box.
• 3) Many disk cleaners and anti-virus type programs can remove data from browsers
  Open their settings and have them leave the browsers alone.
• 4) Mal-ware.

You may be in Private Browsing mode or told Firefox not to remember.

Type about:preferences#privacy<enter> in the address box. The button next to History, select Use Custom Settings.

Turn off Always Use Private Browsing Mode Turn on Remember My Browsing And Download History At the bottom of the page, turn on Clear History When Firefox Closes. At the far right, press the Settings button. Turn on ONLY Cache and Form And Search History leaving the others off.

Macs: Make sure you install Firefox properly and that you do not run Firefox from within the DMG (Disk Images) file. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Firefox used to show at least four years of history. As I documented, Firefox shows no history now.

1) I have 41 Firefox windows up now, none are private.

2) I wrote, "My Settings' History 'Firefox will' has been set to 'Remember History' ", which means Firefox should remember and show all my Firefox history. Therefore, your "You may be in Private Browsing mode or told Firefox not to remember." section seems not to apply to my Firebox not showing my history.

3) I do not use a disk cleaner. I have been using the same anti-virus program, Windows Defender, every since I have owned my laptop in the Spring of 2017. I have not changed any settings in Windows Defender since at least several years ago.

4) Windows Defender has not flagged any malware on my laptop.

Here is some additional information:

When I press on the History menu text, the History menu appears. The bottom of the menu shows a list of 15 web pages that I had visited.

When I press on Hamburger -> History text, the History menu appears on the right side of my Firefox window. The History menu shows a Recent history section. That section shows a list of the last 42 web pages that I had visited.

I went to about:profiles, which shows only one profile.

.

If you use Sync then best is to disconnect Sync temporarily during troubleshooting.

This could be a problem with the places.sqlite and favicons.sqlite files in the Firefox profile folder.

• use the "Places Database" -> "Verify Integrity" button on the "Help -> More Troubleshooting Information" (about:support) page

If errors are reported with "Verify Integrity", close and restart Firefox or reboot and retry.

If "Verify Integrity" cannot repair places.sqlite, rename/remove all places.sqlite and favicons.sqlite files in the Firefox profile folder with Firefox closed. Firefox will rebuild places.sqlite and restore the bookmarks 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
• you lose the history when a new places.sqlite is created

You may have to restore an older bookmarks backup in the bookmarkbackups folder via the Bookmarks Manager (Library).

• Bookmarks -> Show All Bookmarks -> Import & Backup -> Restore
• https://support.mozilla.org/en-US/kb/restore-bookmarks-from-backup-or-move-them

See also:

• https://support.mozilla.org/en-US/kb/fix-bookmarks-and-history-will-not-be-functional
• https://support.mozilla.org/en-US/kb/cant-add-change-or-save-bookmarks

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

• Help -> More Troubleshooting Information -> Profile Folder/Directory:
  Windows: Open Folder; Linux: Open Directory; Mac: Show in Finder
• https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data

Hello cor-el,

Thank you.

Although "Places Database" -> "Verify Integrity" appeared to show no errors, I completed your troubleshooting steps. The bug still exists with the rebuilt places.sqlite file and rebuilt favicons.sqlite file.

The bug: When I try to see my history using the History -> Show All History menu-item or Hamburger -> History -> Manage History menu-item, Firefox displays a Library window without any history.

This is what I did:

1) Disconnected Sync

2) Places Database -> Verify Integrity

Integrity:

> Task: checkIntegrity + The places.sqlite database is sane + The favicons.sqlite database is sane > Task: invalidateCaches + The caches have been invalidated > Task: checkCoherence + The database is coherent > Task: expire + Database cleaned up > Task: originFrecencyStats + Recalculated origin frecency stats > Task: vacuum + Initial database size is 46080KiB + The database has been vacuumed + Final database size is 46080KiB > Task: stats + Places.sqlite size is 46080KiB + Favicons.sqlite size is 7360KiB + pragma_user_version is 59 + pragma_page_size is 32768 + pragma_cache_size is -2048 + pragma_journal_mode is wal + pragma_synchronous is 1 + History can store a maximum of 139439 unique pages + Table moz_places has 80174 records + Table moz_historyvisits has 145603 records + Table moz_inputhistory has 1 records + Table moz_hosts has 0 records + Table moz_bookmarks has 57 records + Table moz_bookmarks_deleted has 0 records + Table moz_keywords has 0 records + Table sqlite_sequence has 1 records + Table moz_anno_attributes has 3 records + Table moz_annos has 53491 records + Table moz_items_annos has 0 records + Table sqlite_stat1 has 18 records + Table moz_meta has 5 records + Table moz_origins has 992 records + Table moz_places_metadata has 0 records + Table moz_places_metadata_search_queries has 0 records + Table moz_places_metadata_snapshots has 0 records + Table moz_places_metadata_snapshots_extra has 0 records + Table moz_places_metadata_snapshots_groups has 0 records + Table moz_places_metadata_groups_to_snapshots has 0 records + Table moz_session_metadata has 0 records + Table moz_session_to_places has 0 records + Pages sequentiality: 24.7 + sqlite_schema: 32KiB (0.1%), 28.2% eff. + moz_inputhistory: 32KiB (0.1%), 0.1% eff. + sqlite_autoindex_moz_inputhistory_1: 32KiB (0.1%), 0.1% eff. + moz_hosts: 32KiB (0.1%), 0% eff. + sqlite_autoindex_moz_hosts_1: 32KiB (0.1%), 0% eff. + moz_bookmarks: 32KiB (0.1%), 13.9% eff. + moz_bookmarks_deleted: 32KiB (0.1%), 0% eff. + sqlite_autoindex_moz_bookmarks_deleted_1: 32KiB (0.1%), 0% eff. + moz_keywords: 32KiB (0.1%), 0% eff. + sqlite_autoindex_moz_keywords_1: 32KiB (0.1%), 0% eff. + sqlite_sequence: 32KiB (0.1%), 0.1% eff. + moz_anno_attributes: 32KiB (0.1%), 0.3% eff. + sqlite_autoindex_moz_anno_attributes_1: 32KiB (0.1%), 0.3% eff. + moz_items_annos: 32KiB (0.1%), 0% eff. + sqlite_stat1: 32KiB (0.1%), 3% eff. + moz_meta: 32KiB (0.1%), 1% eff. + moz_places_metadata: 32KiB (0.1%), 0% eff. + moz_places_metadata_search_queries: 32KiB (0.1%), 0% eff. + sqlite_autoindex_moz_places_metadata_search_queries_1: 32KiB (0.1%), 0% eff. + moz_places_metadata_snapshots: 32KiB (0.1%), 0% eff. + moz_places_metadata_snapshots_extra: 32KiB (0.1%), 0% eff. + moz_places_metadata_snapshots_groups: 32KiB (0.1%), 0% eff. + moz_places_metadata_groups_to_snapshots: 32KiB (0.1%), 0% eff. + moz_session_metadata: 32KiB (0.1%), 0% eff. + sqlite_autoindex_moz_session_metadata_1: 32KiB (0.1%), 0% eff. + moz_session_to_places: 32KiB (0.1%), 0% eff. + moz_bookmarks_itemindex: 32KiB (0.1%), 1.7% eff. + moz_bookmarks_parentindex: 32KiB (0.1%), 1.7% eff. + moz_bookmarks_itemlastmodifiedindex: 32KiB (0.1%), 3% eff. + moz_bookmarks_dateaddedindex: 32KiB (0.1%), 2.6% eff. + moz_bookmarks_guid_uniqueindex: 32KiB (0.1%), 3.3% eff. + moz_keywords_placepostdata_uniqueindex: 32KiB (0.1%), 0% eff. + moz_items_annos_itemattributeindex: 32KiB (0.1%), 0% eff. + moz_places_metadata_placecreated_uniqueindex: 32KiB (0.1%), 0% eff. + moz_origins: 96KiB (0.2%), 37.3% eff. + sqlite_autoindex_moz_origins_1: 96KiB (0.2%), 34.8% eff. + moz_places_visitcount: 736KiB (1.7%), 92.4% eff. + moz_annos_placeattributeindex: 736KiB (1.7%), 92.7% eff. + moz_places_frecencyindex: 800KiB (1.9%), 94% eff. + moz_places_originidindex: 864KiB (2%), 95.4% eff. + moz_places_url_hashindex: 1184KiB (2.8%), 96.6% eff. + moz_places_lastvisitdateindex: 1344KiB (3.2%), 96.7% eff. + moz_historyvisits_fromindex: 1632KiB (3.8%), 97.5% eff. + moz_places_guid_uniqueindex: 1664KiB (3.9%), 96.9% eff. + moz_historyvisits_dateindex: 2432KiB (5.7%), 98.3% eff. + moz_places_hostindex: 2592KiB (6.1%), 98.6% eff. + moz_historyvisits_placedateindex: 2912KiB (6.9%), 98.7% eff. + moz_historyvisits: 3712KiB (8.7%), 98.6% eff. + moz_annos: 5824KiB (13.7%), 98.9% eff. + moz_places: 14752KiB (34.7%), 99.5% eff. > Task: _refreshUI

3) File -> Exit

Firefox disappeared.

4) Firefox: Executed.

Firefox appeared.

Bug still exists: When I try to see my history using the History -> Show All History menu-item or Hamburger -> History -> Manage History menu-item, Firefox displays a Library window without any history.

5) File -> Exit

Firefox disappeared.

6) Renamed places.sqlite and favicons.sqlite files.

7) Firefox: Executed.

Firefox appeared.

Bug still exists: When I try to see my history using the History -> Show All History menu-item or Hamburger -> History -> Manage History menu-item, Firefox displays a Library window without any history..

When I press on the History menu text, the History menu appears. The bottom of the menu shows a list of 2 web pages that I had visited.

When I press on Hamburger -> History text, the History menu appears on the right side of my Firefox window. The History menu shows a Recent history section. That section shows a list of the last 2 web pages that I had visited.

All bookmarks are missing each of their favicons.

.

https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save

Note: Some software, like Advanced SystemCare with Surfing Protection, can protect files in the Firefox profile folder against changes. If you have such software then check the settings or uninstall this software.

Macs: Make sure you install Firefox properly and that you do not run Firefox from within the DMG (Disk Images) file. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

You can restore the favicons by restoring the renamed favicons.sqlite file (i.e. replace the new favicons.sqlite with the renamed favicons.sqlite).

It is weird that only the History Manager isn't showing history.

I did some of the steps from the "Diagnose Firefox issues using Troubleshoot Mode" web page, https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode and the "Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems" web page, https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems. The bug no longer happens, which I did not expect because I did not complete what I thought were crucial steps, turning off hardware acceleration before exiting Firefox and then executing Firefox.

Bug: When I try to see my history using the History -> Show All History menu-item or Hamburger -> History -> Manage History menu-item, Firefox displays a Library window without any history.

I did the following from the "Diagnose Firefox issues using Troubleshoot Mode" web page.

How to start Firefox in Troubleshoot Mode

I clicked the menu button, clicked Help, select Troubleshoot Mode… and clicked Restart in the Restart Firefox in Troubleshoot Mode? dialog.

Troubleshoot Mode window

I clicked on the Open button.

Firefox appeared.

I saw that the problem does not happen in Troubleshoot Mode.

I then did the following from the "Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems " web page.

I clicked the Hamburger menu -> Add-ons and Themes.

I saw that many or all my extensions were disabled, and all Themes were disabled.

I then did some of the steps in the "Turn off hardware acceleration" section.

I clicked the Hamburger menu -> Settings.

I went to the Settings -> General -> Performance section.

I saw that the checkbox for "Use recommended performance settings" was checked.

I unchecked the checkbox.

This appeared: "Use hardware acceleration when available" with its checkbox checked and "Content process limit 8 (default).

I checked the checkbox for "Use recommended performance settings". The "Use hardware …" section disappeared.

I exited Troubleshoot Mode: Firefox -> Exit

I executed Firefox.

I saw that the bug no longer exists. I did not expect this outcome I did not do steps 4 to 6 in the "Turn off hardware acceleration" section because from the "Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems " web page:

4. Uncheck Use hardware acceleration when available. 5. Click the Firefox menu and select Exit. 6. Start Firefox the way you normally do.

That was very good work. Well Done.