Some more bizarre details: I was wrong about the history being gone. It's all there in the side-bar. (The bookmarks are not.) But when I start typing into the bar at the top of the screen, it expands to precisely one site per initial letter (a site that starts with that letter). Also all of my search keywords are gone, but the "New Tab" grid still has nine sites in it.

evan

More info: I also don't seem to be able to bookmark pages. When I click on the star, nothing happens (i.e., the star doesn't get filled in, and the page doesn't get added to the bookmarks list).

evan

Problems with bookmarks and history not working properly can be caused by a corrupted places.sqlite database file.

You can check for problems with the places.sqlite database file in the Firefox Profile Folder.

• http://kb.mozillazine.org/Bookmarks_history_and_toolbar_buttons_not_working_-_Firefox
• https://support.mozilla.org/kb/Bookmarks+not+saved#w_fix-the-bookmarks-file

You can try to check and repair the places database with this extension:

• https://addons.mozilla.org/firefox/addon/places-maintenance/

I tried the places-maintenance add-on, and it claims that my places.sqlite database is both sane and coherent. I asked it to rebuild indices, and that didn't seem to do anything. I don't know if it means anything, but I also have places.sqlite-shm and places.sqlite-wal files. And I confirmed that none of them are read-only.

Can you export the bookmarks to an HTML file on one of the desktop computers?

Did you try to delete the places.sqlite file(s) with Firefox closed?

Problems with the bookmarks getting lost and not being able to restore them are most likely a problem with a corrupted places.sqlite file.
If the problems are worse then Firefox may not be able to repair the database and only deleting places.sqlite will work.

I didn't try exporting them as HTML, but I was able to export them as JSON (using "Backup..." on the "Show All Bookmarks" dialog). The wedged machine was unable to read them in, claiming that it was "unable to process" the file. I haven't tried deleting the places.sqlite file, as that seemed a bit drastic.

If you believe that everything that Firefox stores is local to the profile directory, perhaps the easiest thing to try is to simply restore that directory from last night's backup and see if that fixes things. Does that make sense?

I think that the only way to recover from this will be to delete the places.sqlite file or move the file to another folder or rename the file as a test (places.sqlite.sav) to force Firefox to create a new file.
There shouldn't be any problems with restoring a JSON backup unless the file is really corrupted.

• Bookmarks > Show All Bookmarks > Import & Backup > Restore > Choose File

• http://kb.mozillazine.org/Backing_up_and_restoring_bookmarks_-_Firefox

Deleting places.sqlite and doing a restore from a backup from another system seems to have done the trick. (It lost all of the favicons, but that's not a big deal.)

Thanks.