Firefox about:config settings

# General:
browser.urlbar.trimURLs = false;
browser.quitShortcut.disabled = true;
# (you might want to add some more from: https://github.com/pyllyukko/user.js/blob/master/user.js)

# Tracking:
privacy.donottrackheader.enabled = true;
privacy.trackingprotection.enabled = true;
privacy.trackingprotection.socialtracking.enabled = true;

# Extensions:
extensions.pocket.enabled = false;
extensions.screenshots.disabled = true;

# Tabs in dev-tools you might disable:
devtools.accessibility.enabled = false;
devtools.memory.enabled = false;
devtools.storage.enabled = false;
devtools.styleeditor.enabled = false;
devtools.performance.enabled = false;