--- a/b2g/app/b2g.js
+++ b/b2g/app/b2g.js
@@ -446,26 +446,16 @@ pref("full-screen-api.enabled", true);
 // fill the whole screen, we'll just make the content fill the client window,
 // i.e. it won't give the impression to content that the number of device
 // screen pixels changes!
 pref("full-screen-api.ignore-widgets", true);
 #endif
 
 pref("media.volume.steps", 10);
 
-#ifdef ENABLE_MARIONETTE
-//Enable/disable marionette server, set listening port
-pref("marionette.defaultPrefs.enabled", true);
-pref("marionette.defaultPrefs.port", 2828);
-#ifndef MOZ_WIDGET_GONK
-// On desktop builds, we need to force the socket to listen on localhost only
-pref("marionette.force-local", true);
-#endif
-#endif
-
 #ifdef MOZ_UPDATER
 // When we're applying updates, we can't let anything hang us on
 // quit+restart.  The user has no recourse.
 pref("shutdown.watchdog.timeoutSecs", 10);
 // Timeout before the update prompt automatically installs the update
 pref("b2g.update.apply-prompt-timeout", 60000); // milliseconds
 // Amount of time to wait after the user is idle before prompting to apply an update
 pref("b2g.update.apply-idle-timeout", 600000); // milliseconds
@@ -812,18 +802,17 @@ pref("disk_space_watcher.enabled", true)
 // SNTP preferences.
 pref("network.sntp.maxRetryCount", 10);
 pref("network.sntp.refreshPeriod", 86400); // In seconds.
 pref("network.sntp.pools", // Servers separated by ';'.
      "0.pool.ntp.org;1.pool.ntp.org;2.pool.ntp.org;3.pool.ntp.org");
 pref("network.sntp.port", 123);
 pref("network.sntp.timeout", 30); // In seconds.
 
-// Allow ADB to run for this many hours before disabling
-// (only applies when marionette is disabled)
+// Allow ADB to run for this many hours before disabling.
 // 0 disables the timer.
 pref("b2g.adb.timeout-hours", 12);
 
 // InputMethod so we can do soft keyboards
 pref("dom.mozInputMethod.enabled", true);
 
 // Absolute path to the devtool unix domain socket file used
 // to communicate with a usb cable via adb forward

--- a/b2g/chrome/content/devtools/adb.js
+++ b/b2g/chrome/content/devtools/adb.js
@@ -161,29 +161,16 @@ var AdbController = {
     let usbFuncActive = this.umsActive || isDebugging;
     usbFuncActive |= (sysUsbConfig.indexOf("rndis") >= 0);
     usbFuncActive |= (sysUsbConfig.indexOf("mtp") >= 0);
 
     let enableAdb = this.remoteDebuggerEnabled &&
       (!(this.lockEnabled && this.locked) || usbFuncActive);
 
     let useDisableAdbTimer = true;
-    try {
-      if (Services.prefs.getBoolPref("marionette.defaultPrefs.enabled")) {
-        // Marionette is enabled. Marionette requires that adb be on (and also
-        // requires that remote debugging be off). The fact that marionette
-        // is enabled also implies that we're doing a non-production build, so
-        // we want adb enabled all of the time.
-        enableAdb = true;
-        useDisableAdbTimer = false;
-      }
-    } catch (e) {
-      // This means that the pref doesn't exist. Which is fine. We just leave
-      // enableAdb alone.
-    }
 
     // Check wakelock to prevent adb from disconnecting when phone is locked
     let lockFile = Cc['@mozilla.org/file/local;1'].createInstance(Ci.nsIFile);
     lockFile.initWithPath('/sys/power/wake_lock');
     if(lockFile.exists()) {
       let foStream = Cc["@mozilla.org/network/file-input-stream;1"]
             .createInstance(Ci.nsIFileInputStream);
       let coStream = Cc["@mozilla.org/intl/converter-input-stream;1"]

--- a/b2g/config/mozconfigs/ics_armv7a_gecko/debug
+++ b/b2g/config/mozconfigs/ics_armv7a_gecko/debug
@@ -7,14 +7,13 @@ ac_add_options --enable-b2g-camera
 
 ac_add_options --target=arm-linux-androideabi
 ac_add_options --with-gonk="$topsrcdir/gonk-toolchain"
 export TOOLCHAIN_HOST=linux-x86
 export GONK_PRODUCT=generic
 ac_add_options --with-gonk-toolchain-prefix="$topsrcdir/gonk-toolchain/prebuilt/$TOOLCHAIN_HOST/toolchain/arm-linux-androideabi-4.4.x/bin/arm-linux-androideabi-"
 ac_add_options --enable-debug-symbols
 ac_add_options --enable-debug
-ENABLE_MARIONETTE=1
 
 # Enable dump() from JS.
 export CXXFLAGS="-DMOZ_ENABLE_JS_DUMP -include $topsrcdir/gonk-toolchain/gonk-misc/Unicode.h -include $topsrcdir/gonk-toolchain/system/vold/ResponseCode.h"
 
 . "$topsrcdir/b2g/config/mozconfigs/common.override"

--- a/b2g/config/mozconfigs/ics_armv7a_gecko/nightly
+++ b/b2g/config/mozconfigs/ics_armv7a_gecko/nightly
@@ -8,14 +8,13 @@ ac_add_options --enable-updater
 
 ac_add_options --target=arm-linux-androideabi
 ac_add_options --with-gonk="$topsrcdir/gonk-toolchain"
 export TOOLCHAIN_HOST=linux-x86
 export GONK_PRODUCT=generic
 ac_add_options --with-gonk-toolchain-prefix="$topsrcdir/gonk-toolchain/prebuilt/$TOOLCHAIN_HOST/toolchain/arm-linux-androideabi-4.4.x/bin/arm-linux-androideabi-"
 ac_add_options --enable-debug-symbols
 # ac_add_options --enable-profiling
-ENABLE_MARIONETTE=1
 
 # Enable dump() from JS.
 export CXXFLAGS="-DMOZ_ENABLE_JS_DUMP -include $topsrcdir/gonk-toolchain/gonk-misc/Unicode.h -include $topsrcdir/gonk-toolchain/system/vold/ResponseCode.h"
 
 . "$topsrcdir/b2g/config/mozconfigs/common.override"

--- a/b2g/config/mozconfigs/linux32_gecko/debug
+++ b/b2g/config/mozconfigs/linux32_gecko/debug
@@ -18,17 +18,16 @@ export MOZILLA_OFFICIAL=1
 
 export MOZ_TELEMETRY_REPORTING=1
 
 # Use sccache
 no_sccache=
 
 #B2G options
 ac_add_options --enable-application=b2g
-ENABLE_MARIONETTE=1
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 GAIADIR=$topsrcdir/gaia
 
 # Include Firefox OS fonts.
 MOZTTDIR=$topsrcdir/moz-tt
 
 . "$topsrcdir/b2g/config/mozconfigs/common.override"

--- a/b2g/config/mozconfigs/macosx64_gecko/debug
+++ b/b2g/config/mozconfigs/macosx64_gecko/debug
@@ -16,17 +16,16 @@ export MOZILLA_OFFICIAL=1
 export MOZ_TELEMETRY_REPORTING=1
 
 #ac_add_options --with-macbundlename-prefix=Firefox
 
 # B2G Stuff
 ac_add_options --enable-application=b2g
 ac_add_options --enable-debug-symbols
 ac_add_options --enable-debug
-ENABLE_MARIONETTE=1
 
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 GAIADIR=$topsrcdir/gaia
 
 # Include Firefox OS fonts.
 MOZTTDIR=$topsrcdir/moz-tt
 

--- a/b2g/config/mozconfigs/win32_gecko/debug
+++ b/b2g/config/mozconfigs/win32_gecko/debug
@@ -12,17 +12,16 @@ ac_add_options --enable-debug
 export MOZILLA_OFFICIAL=1
 
 export MOZ_TELEMETRY_REPORTING=1
 
 . $topsrcdir/build/win32/mozconfig.vs-latest
 
 # B2G Options
 ac_add_options --enable-application=b2g
-ENABLE_MARIONETTE=1
 
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 GAIADIR=$topsrcdir/gaia
 
 # Include Firefox OS fonts.
 MOZTTDIR=$topsrcdir/moz-tt
 

--- a/b2g/graphene/config/horizon-mozconfigs/linux32/debug
+++ b/b2g/graphene/config/horizon-mozconfigs/linux32/debug
@@ -14,12 +14,11 @@ STRIP_FLAGS="--strip-debug"
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 # Use sccache
 no_sccache=
 . "$topsrcdir/build/mozconfig.cache"
 
 # graphene options
-ENABLE_MARIONETTE=1
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 . "$topsrcdir/b2g/graphene/config/horizon-mozconfigs/common.override"

--- a/b2g/graphene/config/horizon-mozconfigs/linux64/debug
+++ b/b2g/graphene/config/horizon-mozconfigs/linux64/debug
@@ -14,12 +14,11 @@ STRIP_FLAGS="--strip-debug"
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 # Use sccache
 no_sccache=
 . "$topsrcdir/build/mozconfig.cache"
 
 # graphene options
-ENABLE_MARIONETTE=1
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 . "$topsrcdir/b2g/graphene/config/horizon-mozconfigs/common.override"

--- a/b2g/graphene/config/horizon-mozconfigs/macosx64/debug
+++ b/b2g/graphene/config/horizon-mozconfigs/macosx64/debug
@@ -11,13 +11,12 @@ ac_add_options --enable-js-diagnostics
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 #ac_add_options --with-macbundlename-prefix=Firefox
 
 # graphene Stuff
 ac_add_options --enable-debug-symbols
 ac_add_options --enable-debug
-ENABLE_MARIONETTE=1
 
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 . "$topsrcdir/b2g/graphene/config/horizon-mozconfigs/common.override"

--- a/b2g/graphene/config/horizon-mozconfigs/win32/debug
+++ b/b2g/graphene/config/horizon-mozconfigs/win32/debug
@@ -7,13 +7,11 @@ ac_add_options --enable-debug
 ac_add_options --enable-js-diagnostics
 
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 . $topsrcdir/build/win32/mozconfig.vs-latest
 
 # graphene Options
-ENABLE_MARIONETTE=1
-
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 . "$topsrcdir/b2g/graphene/config/mozconfigs/common.override"

--- a/b2g/graphene/config/mozconfigs/linux32/debug
+++ b/b2g/graphene/config/mozconfigs/linux32/debug
@@ -14,12 +14,11 @@ STRIP_FLAGS="--strip-debug"
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 # Use sccache
 no_sccache=
 . "$topsrcdir/build/mozconfig.cache"
 
 # graphene options
-ENABLE_MARIONETTE=1
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 . "$topsrcdir/b2g/graphene/config/mozconfigs/common.override"

--- a/b2g/graphene/config/mozconfigs/linux64/debug
+++ b/b2g/graphene/config/mozconfigs/linux64/debug
@@ -14,12 +14,11 @@ STRIP_FLAGS="--strip-debug"
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 # Use sccache
 no_sccache=
 . "$topsrcdir/build/mozconfig.cache"
 
 # graphene options
-ENABLE_MARIONETTE=1
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 . "$topsrcdir/b2g/graphene/config/mozconfigs/common.override"

--- a/b2g/graphene/config/mozconfigs/macosx64/debug
+++ b/b2g/graphene/config/mozconfigs/macosx64/debug
@@ -11,13 +11,12 @@ ac_add_options --enable-js-diagnostics
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 #ac_add_options --with-macbundlename-prefix=Firefox
 
 # graphene Stuff
 ac_add_options --enable-debug-symbols
 ac_add_options --enable-debug
-ENABLE_MARIONETTE=1
 
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 . "$topsrcdir/b2g/graphene/config/mozconfigs/common.override"

--- a/b2g/graphene/config/mozconfigs/win32/debug
+++ b/b2g/graphene/config/mozconfigs/win32/debug
@@ -7,13 +7,11 @@ ac_add_options --enable-debug
 ac_add_options --enable-js-diagnostics
 
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 . $topsrcdir/build/win32/mozconfig.vs-latest
 
 # graphene Options
-ENABLE_MARIONETTE=1
-
 export CXXFLAGS=-DMOZ_ENABLE_JS_DUMP
 
 . "$topsrcdir/b2g/grapheneconfig/mozconfigs/common.override"

--- a/b2g/graphene/graphene.js
+++ b/b2g/graphene/graphene.js
@@ -42,18 +42,14 @@ pref("app.update.url", "https://aus4.moz
 pref("b2g.nativeWindowGeometry.width", 700);
 pref("b2g.nativeWindowGeometry.height", 600);
 pref("b2g.nativeWindowGeometry.screenX", -1); // center
 pref("b2g.nativeWindowGeometry.screenY", -1); // center
 pref("b2g.nativeWindowGeometry.fullscreen", false);
 
 pref("media.useAudioChannelService", false);
 
-#ifdef ENABLE_MARIONETTE
-pref("b2g.is_mulet", true);
-#endif
-
 // Most DevTools prefs are set from the shared file
 // devtools/client/preferences/devtools.js, but this one is currently set
 // per-app or per-channel.
 // Number of usages of the web console or scratchpad. If this is less than 5,
 // then pasting code into the web console or scratchpad is disabled
 pref("devtools.selfxss.count", 5);

--- a/b2g/installer/Makefile.in
+++ b/b2g/installer/Makefile.in
@@ -36,20 +36,16 @@ ifdef WIN_UCRT_REDIST_DIR
 DEFINES += -DMOZ_PACKAGE_WIN_UCRT_DLLS=1
 endif
 endif
 
 ifdef MOZ_DEBUG
 DEFINES += -DMOZ_DEBUG=1
 endif
 
-ifdef ENABLE_MARIONETTE
-DEFINES += -DENABLE_MARIONETTE=1
-endif
-
 MOZ_PACKAGER_MINIFY=1
 
 ifeq (cocoa,$(MOZ_WIDGET_TOOLKIT))
 ifndef _APPNAME
 _APPNAME = $(MOZ_MACBUNDLE_NAME)
 endif
 ifndef _BINPATH
 _BINPATH = /$(_APPNAME)/Contents/MacOS

--- a/b2g/installer/package-manifest.in
+++ b/b2g/installer/package-manifest.in
@@ -763,22 +763,16 @@ bin/libfreebl_32int64_3.so
 @BINPATH@/ssltunnel
 #endif
 #endif
 @RESPATH@/chrome/icons/
 @RESPATH@/chrome/chrome@JAREXT@
 @RESPATH@/chrome/chrome.manifest
 @RESPATH@/components/B2GComponents.manifest
 @BINPATH@/@DLL_PREFIX@omxplugin@DLL_SUFFIX@
-#if defined(ENABLE_MARIONETTE) || !defined(MOZ_WIDGET_GONK)
-@RESPATH@/chrome/marionette@JAREXT@
-@RESPATH@/chrome/marionette.manifest
-@RESPATH@/components/marionette.manifest
-@RESPATH@/components/marionette.js
-#endif
 @RESPATH@/components/AlertsService.js
 @RESPATH@/components/ContentPermissionPrompt.js
 @RESPATH@/components/DirectoryProvider.js
 @RESPATH@/components/ProcessGlobal.js
 @RESPATH@/components/OMAContentHandler.js
 @RESPATH@/components/RecoveryService.js
 @RESPATH@/components/MailtoProtocolHandler.js
 @RESPATH@/components/SmsProtocolHandler.js