What do you mean with the History tab?

Is that the History Manager (Library) or the History menu in the Firefox menu button drop down list?

• History > Show All History

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

• 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

Note that removing places.sqlite will remove all history items and there is no easy backup of history items possible apart from a copy and past of history items to a bookmarks folder.

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

• Do not click the Reset button on the Safe mode start window or otherwise make changes.

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

Firefox menu drop down History. Seems reasonable that the issue has to do with the places.sqlite file. Some time recently the file was changed to places.sqlite.corrupt and another places sqlite was created. I have not idea how since it was not done manually. Must have been a recovery by Firefox. Since the sidebar points to the correct file, how do I get the drop down history to point to the correct file?