how do I show all of last months (September) history?
When I list last months history (September) it does not show the entire month, it only lists the last 10 days or so. How do I show the entire last month. History is supposed to be saved for 90 days, but if I look in the tech support page it shows the expire date is set to 20 days but if you look in options it is set to 90 days. If so, where can I find the history?
Opaite Mbohovái (1)
The pref setting browser.history_expire_days of 20 will override the setting in Tools > Options, so you have only history from the last 20 days and older history is gone.
You will have to reset the pref browser.history_expire_days to the default (180) or at least increase the value to keep more history.
To open the about:config page, type about:config in the location (address) bar and press the "Enter" key, just like you type the url of a website to open a website.
If you see a warning then you can confirm that you want to access that page.