Firefox keeps several tables of "history": * URLs you have opened (for example, [https://support.mozilla.org/en-US/questions/1130771 https://support.mozilla.org/en-US/questions/1130771]) * Dates/times associated with your visits to those URLs * Servers you have visited (for example, support.mozilla''.''org), used for the in-URL-bar auto-fill feature When you clear history, the first two categories are erased (except for URLs that are also bookmarked) but the third category is not. Is that whre you notice this problem? In fact, I'm not aware of a built-in way to clear that table (moz_hosts). There are a couple of somewhat difficult ways to do it described in this thread: [https://support.mozilla.org/questions/1109416 Unable to remove suggestion from address bar] Alternately, you could hide the database file to force Firefox to create a fresh one. Firefox should restore your last automatic bookmark backup as part of that process, but I suggest making a couple safety backups first. (1) Create an extra bookmark backup using the steps in this article: [[Restore bookmarks from backup or move them to another computer]]. And for good measure, an HTML-format export: [[Export Firefox bookmarks to an HTML file to back up or transfer bookmarks]] (2) Open your current Firefox settings (AKA Firefox profile) folder using either * "3-bar" menu button > "?" button > 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 "Show in Finder" button. This should launch a new window listing various files and folders. Leaving that window open, switch back to Firefox and Exit, either: * "3-bar" menu button > "power" button * (menu bar) File > Exit (3) Pause while Firefox finishes its cleanup -- give it a good 15-30 seconds -- then <u>rename</u> '''places.sqlite''' to something like places.old. The reason for renaming rather than deleting is in case Firefox is not able to restore your bookmark backup. If you see other similarly named files like places.sqlite-shm and/or places.sqlite-wal, you can delete those. (4) Start Firefox back up again. When it fails to find places.sqlite, Firefox should create a new one and restore your bookmarks from your last automatic backup. Are the bookmarks complete? If not, you can restore your manual backup using the steps in the above article.

You can check for problems with the <b>places.sqlite</b> database (bookmarks and history) in the Firefox profile folder. *https://addons.mozilla.org/firefox/addon/places-maintenance/ See also: *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