Safebrowsing prefs got renamed and features got added. We should make sure Safebrowsing is still disablled in ESR 52, though. For starters we could set browser.safebrowsing.downloads.enabled = false browser.safebrowsing.downloads.remote.enabled = false browser.safebrowsing.malware.enabled = false browser.safebrowsing.phishing.enabled = false browser.safebrowsing.blockedURIs.enabled = false