On 2019-03-12, David E. Ross wrote:
On 3/11/2019 3:57 PM, wrote:
I am sure most any user of Firefox has noticed in the last few months that it has gotten to be a real
memory hog.

I have been looking for ways to decrease memory usage and release old memory and came across a new one
on me that I want to share with whoever else has not heard of it but has memory bloat problems from the
application.

enter "about:memory" in the same way you would enter "about:config"

click on "minimize memory usage". A rollover will disclose what it does.


The amount of memory used is affected by the complexity of the Web pages
you are viewing, the sizes of any images in those pages, and the number
of tabs you have open.

And you should not forget all new silent added features:
https://support.mozilla.org/en-US/questions/1181551

This is what I always do with Firefox ESR on another operating system.
I think its always wise to choose Firefox ESR. (Extended Support Release)


Find and temporary rename:

to
to
to
to
to
to
to
to
to

Windows:
cd C:\Program Files (x86)\Mozilla Firefox\browser\features
or cd cd C:\Program Files\Mozilla Firefox\browser\features
ren *.xpi *.bak

Linux:
cd /usr/lib/firefox-esr/browser/features
sudo rename 's/\.xpi$/\.bak/' *.xpi

*notice: after a each Firefox update you have to repeat renaming*


And here are some prefs of my *initial single-launch* user.js for
Firefox and Thunderbird, which you can also alter in about:config

user_pref("accessibility.typeaheadfind.flashBar", 0);
//user_pref("app.update.auto", false);
user_pref("app.update.lastUpdateTime.telemetry_mod ules_ping", 0);
user_pref("app.update.lastUpdateTime.xpi-signature-verification", 0);
user_pref("beacon.enabled", false);
user_pref("breakpad.reportURL", "");
//user_pref("browser.bookmarks.max_backups", 0);
//user_pref("browser.cache.disk.capacity", 358400);
//user_pref("browser.cache.disk.enable", false);
user_pref("browser.cache.disk.filesystem_reported" , 1);
//user_pref("browser.cache.memory.enable", false);
user_pref("browser.cache.offline.enable", false);
//user_pref("browser.chrome.favicons", false);
//user_pref("browser.chrome.site_icons", false);
user_pref("browser.display.use_document_fonts", 0);
user_pref("browser.formfill.enable", false);
user_pref("browser.safebrowsing.blockedURIs.enable d", false);
user_pref("browser.safebrowsing.downloads.enabled" , false);
user_pref("browser.safebrowsing.downloads.remote.b lock_dangerous", false);
user_pref("browser.safebrowsing.downloads.remote.b lock_dangerous_host", false);
user_pref("browser.safebrowsing.downloads.remote.b lock_potentially_unwanted", false);
user_pref("browser.safebrowsing.downloads.remote.b lock_uncommon", false);
user_pref("browser.safebrowsing.downloads.remote.e nabled", false);
user_pref("browser.safebrowsing.downloads.remote.u rl", "");
user_pref("browser.safebrowsing.enabled", false);
user_pref("browser.safebrowsing.malware.enabled", false);
user_pref("browser.safebrowsing.phishing.enabled", false);
user_pref("browser.search.countryCode", "US");
user_pref("browser.search.geoip.url", "");
user_pref("browser.search.region", "US");
user_pref("browser.search.suggest.enabled", false);
user_pref("browser.search.update", false);
user_pref("browser.urlbar.autocomplete.enabled", false);
user_pref("calendar.useragent.extra", "");
user_pref("chat.browserRequest.disableJavascript", true);
user_pref("chat.dns.srv.disable", true);
//user_pref("chat.twitter.consumerKey", "");
//user_pref("chat.twitter.consumerSecret", "");
user_pref("datareporting.healthreport.about.report Url", "data:text/plain,");
user_pref("datareporting.healthreport.service.enab led", false);
user_pref("datareporting.healthreport.uploadEnable d", false);
user_pref("datareporting.policy.dataSubmissionEnab led", false);
user_pref("device.sensors.enabled", false);
user_pref("devtools.chrome.enabled", false);
user_pref("devtools.debugger.remote-enabled", false);
user_pref("devtools.gcli.imgurClientID", "");
user_pref("devtools.remote.wifi.scan", false);
user_pref("devtools.webide.enabled", false);
user_pref("dom.battery.enabled", false);
user_pref("dom.enable_performance", false);
user_pref("dom.enable_performance_navigation_timin g", false);
user_pref("dom.enable_performance_observer", false);
user_pref("dom.enable_resource_timing", false);
user_pref("dom.enable_user_timing", false);
user_pref("dom.event.clipboardevents.enabled", false);
user_pref("dom.event.contextmenu.enabled", false);
user_pref("dom.gamepad.enabled", false);
user_pref("dom.indexedDB.enabled", false);
user_pref("dom.ipc.plugins.reportCrashURL", false);
user_pref("dom.storage.enabled", false);
//user_pref("extensions.blocklist.enabled", false);
user_pref("extensions.blocklist.pingCountTotal", 2);
user_pref("extensions.blocklist.pingCountVersion", 0);
user_pref("extensions.databaseSchema", 25);
user_pref("extensions.getAddons.cache.enabled", false);
user_pref("extensions.getAddons.databaseSchema", 5);
user_pref("extensions.pendingOperations", false);
user_pref("extensions.systemAddonSet", "{\"schema\":1,\"addons\":{}}");
user_pref("extensions.ui.dictionary.hidden", true);
user_pref("extensions.ui.lastCategory", "addons://list/extension");
user_pref("extensions.ui.locale.hidden", false);
user_pref("extensions.update.enabled", false);
user_pref("extensions.webextensions.protocol.remot e", false);
user_pref("gecko.handlerService.migrated", true);
//user_pref("general.useragent.override", "");
user_pref("geo.enabled", false);
//user_pref("gfx.downloadable_fonts.enabled", false);
//user_pref("gfx.font_rendering.opentype_svg.enabled ", false);
user_pref("intl.regional_prefs.use_os_locales", false);
//user_pref("javascript.enabled", false);
user_pref("javascript.options.ion", false);
user_pref("javascript.options.native_regexp", false);
//user_pref("layout.css.visited_links_enabled", false);
//...
//user_pref("media.cache_size", 0);
user_pref("media.encoder.webm.enabled", false);
user_pref("media.ffvpx.enabled", false);
user_pref("media.flac.enabled", false);
user_pref("media.getusermedia.aec_enabled", false);
user_pref("media.gmp.storage.version.observed", 1);
user_pref("media.hardware-video-decoding.enabled", false);
user_pref("media.mediasource.enabled", false);
user_pref("media.mediasource.mp4.enabled", false);
user_pref("media.mediasource.webm.audio.enabled", false);
user_pref("media.mp4.enabled", false);
user_pref("media.navigator.audio.full_duplex", false);
user_pref("media.navigator.audio.use_fec", false);
user_pref("media.navigator.enabled", false);
user_pref("media.ogg.enabled", false);
user_pref("media.ogg.flac.enabled", false);
user_pref("media.opus.enabled", false);
user_pref("media.peerconnection.dtmf.enabled", false);
user_pref("media.peerconnection.enabled", false);
user_pref("media.peerconnection.ice.default_addres s_only", true);
user_pref("media.peerconnection.identity.enabled", false);
user_pref("media.peerconnection.identity.timeout", 1);
user_pref("media.peerconnection.turn.disable", true);
user_pref("media.peerconnection.use_document_icese rvers", false);
user_pref("media.peerconnection.video.enabled", false);
user_pref("media.peerconnection.video.vp9_enabled" , false);
user_pref("media.video_stats.enabled", false);
user_pref("media.wave.enabled", false);
user_pref("media.webm.enabled", false);
user_pref("media.wmf.dxva.d3d11.enabled", false);
user_pref("media.wmf.dxva.enabled", false);
user_pref("media.wmf.enabled", false);
//...
user_pref("network.allow-experiments", false);
user_pref("network.cookie.cookieBehavior", 1);
user_pref("network.cookie.lifetimePolicy", 2);
user_pref("network.cookie.prefsMigrated", true);
user_pref("network.dns.disablePrefetch", true);
user_pref("network.http.altsvc.enabled", false);
user_pref("network.http.altsvc.oe", false);
user_pref("network.http.connection-retry-timeout", 0);
user_pref("network.http.max-persistent-connections-per-proxy", 256);
user_pref("network.http.pipelining", true);
user_pref("network.http.pipelining.aggressive", true);
user_pref("network.http.pipelining.maxrequests", 12);
user_pref("network.http.pipelining.read-timeout", 60000);
user_pref("network.http.pipelining.reschedule-timeout", 15000);
user_pref("network.http.pipelining.ssl", true);
user_pref("network.http.proxy.pipelining", true);
user_pref("network.http.spdy.enabled", false);
user_pref("network.online", false);
user_pref("network.predictor.cleaned-up", true);
user_pref("network.predictor.enabled", false);
user_pref("network.prefetch-next", false);
user_pref("network.protocol-handler.warn-external.file", true);
user_pref("network.protocol-handler.warn-external.ftp", true);
user_pref("network.protocol-handler.warn-external.http", true);
user_pref("network.protocol-handler.warn-external.https", true);
//user_pref("network.proxy.socks", "127.0.0.1");
//user_pref("network.proxy.socks_port", 9150);
//user_pref("network.proxy.socks_remote_dns", true);
//user_pref("network.proxy.type", 1);
//user_pref("network.security.ports.banned", "9050,9051,9150,9151");
user_pref("network.websocket.delay-failed-reconnects", false);
user_pref("network.websocket.enabled", false);
user_pref("offline.autoDetect", false);
user_pref("offline.download.download_messages", 2);
user_pref("offline.startup_state", 1);
//user_pref("permissions.default.image", 3);
user_pref("places.history.enabled", false);
user_pref("places.history.expiration.transient_cur rent_max_pages", 104858);
user_pref("pref.privacy.disable_button.cookie_exce ptions", false);
user_pref("pref.privacy.disable_button.view_passwo rds", false);
user_pref("privacy.firstparty.isolate", true);
user_pref("privacy.resistFingerprinting", true);
user_pref("privacy.resistFingerprinting.autoDeclin eNoUserInputCanvasPrompts", false);
//...
user_pref("reader.parse-on-load.enabled", false);
user_pref("rss.display.disallow_mime_handlers", 3);
user_pref("rss.display.html_as", 1);
user_pref("rss.display.prefer_plaintext", true);
user_pref("rss.show.content-base", 1);
user_pref("security.cert_pinning.enforcement_level ", 2);
user_pref("security.disable_button.openCertManager ", false);
user_pref("security.disable_button.openDeviceManag er", false);
user_pref("security.enable_ssl3", false);
user_pref("security.enable_tls_session_tickets", false);
user_pref("security.family_safety.mode", 0);
user_pref("security.ssl.require_safe_negotiation", true);
user_pref("security.ssl.treat_unsafe_negotiation_a s_broken", true);
user_pref("security.tls.version.max", 3);
user_pref("security.tls.version.min", 3);
user_pref("security.warn_entering_weak", true);
user_pref("security.warn_submit_insecure", true);
user_pref("signon.autofillForms", false);
user_pref("signon.importedFromSqlite", true);
user_pref("storage.vacuum.last.index", 0);
user_pref("svg.disabled", true);
user_pref("toolkit.telemetry.cachedClientID", "");
user_pref("toolkit.telemetry.infoURL", "");
user_pref("toolkit.telemetry.prompted", 2);
user_pref("toolkit.telemetry.rejected", true);
user_pref("toolkit.telemetry.server", "");
user_pref("toolkit.telemetry.unified", false);
user_pref("webgl.disable-extensions", true);
user_pref("webgl.disabled", true);
user_pref("webgl.enable-webgl2", false);
user_pref("webgl.min_capability_mode", true);

EOF