In TOOLS then OPTIONS then PRIVACY

thank you

This one is hidden a little but, here is how to get at it. Go to your preferences, usually Edit > Preferences. Click on the Privacy tab, under the History heading you will see 'Firefox will" followed by a drop down list.

In this list selected 'Use custom settings for history'. A bunch of options will be exposed now, the last one is the one you are looking for. When you tick this, the settings button to the right of it will become active.

Clicking this will allow you to customise exactly which items you want to clear from history on exit, very useful if you for example only want to clear browsing history and cache.

Thanks for using Firefox, Schalk