+### Preferences
+Set and lock certain preferences.
+
+**Compatibility:** See below\
+**CCK2 Equivalent:** `preferences`\
+**Preferences Affected:** See below
+
+| Preference | Type | Compatibility | Default
+| --- | --- | --- | ---
+| accessibility.force_disabled | integer | Firefox 70, Firefox ESR 68.2 | 0
+| If set to 1, platform accessibility is disabled.
+| app.update.auto | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, Firefox doesn't automatically install update.
+| browser.bookmarks.autoExportHTML | boolean | Firefox 70, Firefox ESR 68.2 | false
+| If true, bookmarks are exported on shutdown.
+| browser.bookmarks.file | string | Firefox 70, Firefox ESR 68.2 | N/A
+| If set, the name of the file where bookmarks are exported and imported.
+| browser.bookmarks.restore_default_bookmarks | boolean | Firefox 70, Firefox ESR 68.2 | N/A
+| If true, bookmarks are restored to their defaults.
+| browser.cache.disk.enable | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, don't store cache on the hard drive.
+| ~browser.cache.disk.parent_directory~ | string | Firefox 68, Firefox ESR 68 | Profile temporary directory
+| ~If set, changes the location of the disk cache.~ This policy doesn't work. It's being worked on.
+| browser.fixup.dns_first_for_single_words | boolean | Firefox 68, Firefox ESR 68 | false
+| If true, single words are sent to DNS, not directly to search.
+| browser.newtabpage.activity-stream.default.sites | string | Firefox 72, ESR 68.4 | Locale dependent
+| If set, a list of URLs to use as the default top sites on the new tab page.
+| browser.places.importBookmarksHTML | boolean | Firefox 70, Firefox ESR 68.2
+| If true, bookmarks are always imported on startup.
+| browser.safebrowsing.phishing.enabled | boolean | Firefox 70, Firefox ESR 68.2 | true
+| If false, phishing protection is not enabled (Not recommended)
+| browser.safebrowsing.malware.enabled | boolean | Firefox 70, Firefox ESR 68.2 | true
+| If false, malware protection is not enabled (Not recommended)
+| browser.search.update | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, updates for search engines are not checked.
+| browser.slowStartup.notificationDisabled | boolean | Firefox 70, Firefox ESR 68.2 | false
+| If true, a notification isn't shown if startup is slow.
+| browser.tabs.warnOnClose | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, there is no warning when the browser is closed.
+| browser.taskbar.previews.enable | boolean | Firefox 70, Firefox ESR 68.2 (Windows only) | false
+| If true, tab previews are shown in the Windows taskbar.
+| browser.urlbar.suggest.bookmark | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, bookmarks aren't suggested when typing in the URL bar.
+| browser.urlbar.suggest.history | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, history isn't suggested when typing in the URL bar.
+| browser.urlbar.suggest.openpage | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, open tabs aren't suggested when typing in the URL bar.
+| datareporting.policy.dataSubmissionPolicyBypassNotification | boolean | Firefox 68, Firefox ESR 68 | false
+| If true, don't show the privacy policy tab on first run.
+| dom.allow_scripts_to_close_windows | boolean | Firefox 70, Firefox ESR 68.2 | false
+| If false, web page can close windows.
+| dom.disable_window_flip | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, web pages can focus and activate windows.
+| dom.disable_window_move_resize | boolean | Firefox 68, Firefox ESR 68 | false
+| If true, web pages can't move or resize windows.
+| dom.event.contextmenu.enabled | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, web pages can't override context menus.
+| dom.keyboardevent.keypress.hack.dispatch_non_printable_keys.addl | string | Firefox 68, Firefox ESR 68 | N/A
+| See https://support.mozilla.org/en-US/kb/dom-events-changes-introduced-firefox-66
+| dom.keyboardevent.keypress.hack.use_legacy_keycode_and_charcode.addl | string | Firefox 68, Firefox ESR 68 | N/A
+| See https://support.mozilla.org/en-US/kb/dom-events-changes-introduced-firefox-66
+| dom.xmldocument.load.enabled | boolean | Firefox ESR 68.5 | true.
+| If false, XMLDocument.load is not available.
+| dom.xmldocument.async.enabled | boolean | Firefox ESR 68.5 | true
+| If false, XMLDocument.async is not available.
+| extensions.blocklist.enabled | boolean | Firefox 70, Firefox ESR 68.2 | true
+| If false, the extensions blocklist is not used (Not recommended)
+| extensions.getAddons.showPane | boolean | Firefox 68, Firefox ESR 68 | N/A
+| If false, the Recommendations tab is not displayed in the Add-ons Manager.
+| extensions.htmlaboutaddons.recommendations.enabled | boolean | Firefox 72, Firefox ESR 68.4 | true
+| If false, recommendations are not shown on the Extensions tab in the Add-ons Manager.
+| geo.enabled | boolean | Firefox 70, Firefox ESR 68.2 | true
+| If false, the geolocation API is disabled. | Language dependent
+| intl.accept_languages | string | Firefox 70, Firefox ESR 68.2
+| If set, preferred language for web pages.
+| media.eme.enabled | boolean | Firefox 70, Firefox ESR 68.2 | true
+| If false, Encrypted Media Extensions are not enabled.
+| media.gmp-gmpopenh264.enabled | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, the OpenH264 plugin is not downloaded.
+| media.gmp-widevinecdm.enabled | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, the Widevine plugin is not downloaded.
+| media.peerconnection.enabled | boolean | Firefox 72, Firefox ESR 68.4 | true
+| If false, WebRTC is disabled
+| media.peerconnection.ice.obfuscate_host_addresses.whitelist | string | Firefox 72, Firefox ESR 68.4 | N/A
+| If set, a list of domains for which mDNS hostname obfuscation is
+disabled
+| network.dns.disableIPv6 | boolean | Firefox 68, Firefox ESR 68 | false
+| If true, IPv6 DNS lokoups are disabled.
+| network.IDN_show_punycode | boolean | Firefox 68, Firefox ESR 68 | false
+| If true, display the punycode version of internationalized domain names.
+| places.history.enabled | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, history is not enabled.
+| print.save_print_settings | boolean | Firefox 70, Firefox ESR 68.2 | true
+| If false, print settings are not saved between jobs.
+| security.default_personal_cert | string | Firefox 68, Firefox ESR 68 | Ask Every Time
+| If set to Select Automatically, Firefox automatically chooses the default personal certificate.
+| security.mixed_content.block_active_content | boolean | Firefox 70, Firefox ESR 68.2 | true
+| If false, mixed active content (HTTP and HTTPS) is not blocked.
+| security.osclientcerts.autoload | boolean | Firefox 72, Firefox ESR 68.4 (Windows only) | false
+| If true, client certificates are loaded from the operating system certificate store.
+| security.ssl.errorReporting.enabled | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, SSL errors cannot be sent to Mozilla.
+| security.tls.hello_downgrade_check | boolean | Firefox 72, Firefox ESR 68.4 | true
+| If false, the TLS 1.3 downgrade check is disabled.
+| ui.key.menuAccessKeyFocuses | boolean | Firefox 68, Firefox ESR 68 | true
+| If false, the Alt key doesn't show the menubar on Windows.
+| widget.content.gtk-theme-override | string | Firefox 72, Firefox ESR 68.4 (Linux only) | N/A
+| If set, overrides the GTK theme for widgets.
+#### Windows (GPO)
+```
+Software\Policies\Mozilla\Firefox\Preferences\boolean_preference_name = 0x1 | 0x0
+Software\Policies\Mozilla\Firefox\Preferences\string_preference_name = "string_value"
+```
+#### macOS
+```
+<dict>
+ <key>Preferences</key>
+ <dict>
+ <key>boolean_preference_name</key>
+ <true/> | <false/>
+ <key>string_preference_name</key>
+ <string>string_value</string>
+ </dict>
+</dict>
+```
+#### policies.json
+```
+{
+ "policies": {
+ "Preferences": {
+ "boolean_preference_name": true | false,
+ "string_preference_name": "string_value"
+ }
+ }
+}
+```
+### PromptForDownloadLocation
+Ask where to save each file before downloading.
+
+**Compatibility:** Firefox 68, Firefox ESR 68\
+**CCK2 Equivalent:** N/A\
+**Preferences Affected:** `browser.download.useDownloadDir`
+
+#### Windows (GPO)
+```
+Software\Policies\Mozilla\Firefox\PromptForDownloadLocation = 0x1 | 0x0
+```
+#### macOS
+```
+<dict>
+ <key>PromptForDownloadLocation</key>
+ <true/> | <false/>
+</dict>
+```
+#### policies.json
+```
+{
+ "policies": {
+ "PromptForDownloadLocation": true | false
+ }
+}
+```