Hi ctcollector, sorry to hear about this problem. Your symptoms suggest the Places database that stores bookmarks and history is locked or corrupted.

If you haven't already, could you try doing a regular shutdown and restart of Windows to free up file locks and complete any deferred updates.

Then could you let us know what you get when you run Firefox's "Verify Integrity" function. That's here:

Open Firefox's Troubleshooting Information page using any of these methods:

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

Near the bottom, there is a section titled Places Database -- that's the file which stores history and bookmarks. Click the button labeled Verify Integrity. There may be a 10-15 second delay before results appear.

If all is well, the report that appears below the button should start with:

> Task: checkIntegrity
+ The places.sqlite database is sane
+ The favicons.sqlite database is sane

Does yours say that, or something else? You can select and copy the report, and then paste it into a reply for review and comment.

Before I could run the trouble shooting my bookmarks showed up the next morning. But I did run the report you asked me to and here it is below

Thanks, Jan > 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 76800KiB + The database has been vacuumed + Final database size is 76800KiB > Task: stats + Places.sqlite size is 76800KiB + Favicons.sqlite size is 24736KiB + pragma_user_version is 53 + 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 155422 unique pages + Table moz_origins has 2606 records + Table moz_places has 153196 records + Table moz_historyvisits has 249823 records + Table moz_inputhistory has 5 records + Table moz_bookmarks has 190 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 301 records + Table moz_items_annos has 0 records + Table moz_meta has 7 records + Table sqlite_stat1 has 17 records + Index sqlite_autoindex_moz_origins_1 + Index sqlite_autoindex_moz_inputhistory_1 + Index sqlite_autoindex_moz_bookmarks_deleted_1 + Index sqlite_autoindex_moz_keywords_1 + Index sqlite_autoindex_moz_anno_attributes_1 + Index moz_places_url_hashindex + Index moz_places_hostindex + Index moz_places_visitcount + Index moz_places_frecencyindex + Index moz_places_lastvisitdateindex + Index moz_places_guid_uniqueindex + Index moz_places_originidindex + Index moz_historyvisits_placedateindex + Index moz_historyvisits_fromindex + Index moz_historyvisits_dateindex + Index moz_bookmarks_itemindex + Index moz_bookmarks_parentindex + Index moz_bookmarks_itemlastmodifiedindex + Index moz_bookmarks_dateaddedindex + Index moz_bookmarks_guid_uniqueindex + Index moz_keywords_placepostdata_uniqueindex + Index moz_annos_placeattributeindex + Index moz_items_annos_itemattributeindex > Task: _refreshUI

Accessibility Activated true

Also, Look on your desktop. Do you see a folder called; Old Firefox? Look inside. Look for the folder with the latest creation date.

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

Before I could run the trouble shooting my bookmarks showed up the next morning.

Firefox needed a good night's sleep? More likely, there was a temporary lock on the file, or some kind of permissions problem, that cleared up before your next session.