Firefox - arkenfox user.js
I recently learned about the arkenfox user.js project, which is an easy way to update Firefox’s settings to improve security and privacy.
It suggests you add your own overrides to the bottom of the file. I added these:
/* re-enable location bar using search ***/
user_pref("keyword.enabled", true);
/* override recipe: enable session restore ***/
user_pref("browser.startup.page", 3); // 0102
user_pref("browser.privatebrowsing.autostart", false); // 0110 required if you had it set as true
user_pref("places.history.enabled", true); // 0862 required if you had it set as false
user_pref("browser.sessionstore.privacy_level", 0); // 1003 optional [to restore cookies/formdata]
user_pref("network.cookie.lifetimePolicy", 0); // 2801 optional [so cookies persist]
user_pref("privacy.clearOnShutdown.history", false); // 2811
user_pref("privacy.cpd.history", false); // 2812 to match when you use Ctrl-Shift-Del