diff --git a/extra/firefox-esr/build b/extra/firefox-esr/build
index d496929f..18ba734d 100755
--- a/extra/firefox-esr/build
+++ b/extra/firefox-esr/build
@@ -1,5 +1,9 @@
 #!/bin/sh -e
 
+for patch in *.patch; do
+    patch -p1 < "$patch"
+done
+
 # Build autoconf 2.13 for Firefox's sole use.
 # See: https://bugzilla.mozilla.org/show_bug.cgi?id=104642
 (
@@ -25,33 +29,71 @@
     make
     make install
 )
+export PATH="$PWD/junk/bin:$PATH"
+
+mkdir -p build
+cd build
+
+# Bypass 'ccache' as it's totally useless when building
+# Firefox and only slows things down.
+export CC="${CC:-/usr/bin/gcc}"
+export CXX="${CXX:-/usr/bin/g++}"
 
-export PATH=$PWD/junk/bin:$PATH
 export LDFLAGS="$LDFLAGS -Wl,-rpath=/usr/lib/firefox"
-export CC=${CC:-gcc}
-export CXX=${CXX:-g++}
-
-# Keep memory usage as low as possible.
-export LDFLAGS="$LDFLAGS -Wl,--as-needed -Wl,--no-keep-memory -Wl,--stats"
-export MOZ_LINK_FLAGS="$LDFLAGS"
+export RUSTFLAGS="$RUSTFLAGS -Cdebuginfo=0"
 export MOZ_DEBUG_FLAGS=-g0
-export RUSTFLAGS=-Cdebuginfo=0
+export MOZ_NOSPAM=1
 
-for patch in *.patch; do
-    patch -p1 < "$patch"
-done
+../configure \
+    --prefix=/usr \
+    --libdir=/usr/lib \
+    --enable-official-branding \
+    --enable-optimize="$CFLAGS -w" \
+    --enable-install-strip \
+    --enable-strip \
+    --enable-rust-simd \
+    --enable-application=browser \
+    --enable-release \
+    --enable-alsa \
+    --without-system-nspr \
+    --without-system-nss \
+    --with-system-jpeg \
+    --with-system-zlib \
+    --with-system-bz2 \
+    --with-system-png \
+    --without-system-libvpx \
+    --with-system-pixman \
+    --with-system-ffi \
+    --disable-gconf \
+    --disable-profiling \
+    --disable-accessibility \
+    --disable-tests \
+    --disable-system-extension-dirs \
+    --disable-parental-controls \
+    --disable-debug-symbols \
+    --disable-callgrind \
+    --disable-vtune \
+    --disable-elf-hack \
+    --disable-gold \
+    --disable-jemalloc \
+    --disable-pulseaudio \
+    --disable-startup-notification \
+    --disable-crashreporter \
+    --disable-updater \
+    --disable-dbus \
+    --disable-eme \
+    --disable-necko-wifi
 
-printf 'mk_add_options MOZ_MAKE_FLAGS="%s"\n' \
-    "${MAKEFLAGS:--j1 -l1}" >> mozconfig
-
-MOZ_NOSPAM=1 ./mach build
-DESTDIR="$1" ./mach install
+make
+make DESTDIR="$1" install
 
+# Remove a lot of uneeded "stuff".
 rm -rf "$1/usr/include"
 rm -rf "$1/usr/lib/firefox-devel"
 rm -rf "$1/usr/share/idl"
-rm -rf "$1/usr/lib/firefox/gtk2"
+rm -rf "$1/usr/lib/firefox/gtk2" # Drop GTK+2 runtime dependency.
 rm -f  "$1/usr/lib/firefox/browser/features/fxmonitor@mozilla.org.xpi"
 rm -f  "$1/usr/lib/firefox/browser/features/screenshots@mozilla.org.xpi"
 rm -f  "$1/usr/lib/firefox/browser/features/webcompat-reporter@mozilla.org.xpi"
 rm -f  "$1/usr/lib/firefox/browser/features/webcompat@mozilla.org.xpi"
+rm -f  "$1/usr/lib/firefox/browser/features/doh-rollout@mozilla.org.xpi"
diff --git a/extra/firefox-esr/checksums b/extra/firefox-esr/checksums
index 429e30ee..580bdccc 100644
--- a/extra/firefox-esr/checksums
+++ b/extra/firefox-esr/checksums
@@ -1,7 +1,6 @@
-fa5b2266d225878d4b35694678f79fd7e7a6d3c62759a40326129bd90f63e842  firefox-68.8.0esr.source.tar.xz
+935105e1a8a97d64daffb372690e2b566b5f07641f01470929dbbc82d20d4407  firefox-68.9.0esr.source.tar.xz
 f0611136bee505811e9ca11ca7ac188ef5323a8e2ef19cffd3edb3cf08fd791e  autoconf-2.13.tar.gz
 3dce6601b495f5b3d45b59f7d2492a340ee7e84b5beca17e48f862502bd5603f  yasm-1.3.0.tar.gz
-6e2832f39b8ccbef29f45208adf6b9dcf9c6d940ac211e6da6fa480e5f912e86  mozconfig
 960d82bbfdc88c95f5cb4f2e1c1bf23dae7519b3b7203914d7b3ddbff1ba4c28  stab.h
 315880530f09175788dfa48a1915bfa1e190bfd3e267988b9100cb93006c808c  fix-fortify-system-wrappers.patch
 14f281ee323aa682e04479019171bde243ac6227820856aa03b162179b14bfd9  fix-seccomp-bpf.patch
diff --git a/extra/firefox-esr/depends b/extra/firefox-esr/depends
index baebe51d..9d48cc76 100644
--- a/extra/firefox-esr/depends
+++ b/extra/firefox-esr/depends
@@ -37,8 +37,8 @@ libvpx
 libxcb
 libxshmfence
 llvm          make
-mesa
 m4            make
+mesa
 nasm          make
 nodejs        make
 pango
diff --git a/extra/firefox-esr/files/mozconfig b/extra/firefox-esr/files/mozconfig
deleted file mode 100644
index 35af3fa2..00000000
--- a/extra/firefox-esr/files/mozconfig
+++ /dev/null
@@ -1,58 +0,0 @@
-ac_add_options --prefix=/usr
-ac_add_options --libdir=/usr/lib
-
-ac_add_options --enable-official-branding
-ac_add_options --enable-optimize="$CFLAGS"
-ac_add_options --enable-install-strip
-ac_add_options --enable-strip
-
-ac_add_options --without-system-nspr
-ac_add_options --without-system-nss
-ac_add_options --with-system-jpeg
-ac_add_options --with-system-zlib
-ac_add_options --with-system-bz2
-ac_add_options --with-system-png
-
-# System 'libvpx' is too new.
-ac_add_options --without-system-libvpx
-
-ac_add_options --with-system-pixman
-ac_add_options --with-system-ffi
-
-ac_add_options --disable-gconf
-ac_add_options --disable-profiling
-ac_add_options --disable-accessibility
-ac_add_options --disable-tests
-ac_add_options --disable-system-extension-dirs
-ac_add_options --disable-parental-controls
-ac_add_options --disable-debug-symbols
-ac_add_options --disable-callgrind
-ac_add_options --disable-vtune
-
-# Settings for musl.
-ac_add_options --disable-elf-hack
-ac_add_options --disable-gold
-ac_add_options --disable-jemalloc
-ac_add_options --enable-release
-
-# ALSA/PulseAudio (removed in 70 (still present in 71b4(?!))
-ac_add_options --disable-pulseaudio
-ac_add_options --enable-alsa
-
-ac_add_options --disable-startup-notification
-
-# Respect the user.
-ac_add_options MOZ_SERVICES_METRICS=
-ac_add_options MOZ_PAY=
-ac_add_options MOZ_SERVICES_HEALTHREPORTER=
-ac_add_options MOZ_SERVICES_FXACCOUNTS=
-ac_add_options MOZ_SERVICES_METRICS=
-ac_add_options MOZ_DATA_REPORTING=
-ac_add_options MOZ_DEVICES=
-ac_add_options MOZ_REQUIRE_SIGNING=
-ac_add_options MOZ_TELEMETRY_REPORTING=
-ac_add_options --disable-crashreporter
-ac_add_options --disable-updater
-ac_add_options --disable-dbus
-ac_add_options --disable-eme
-ac_add_options --disable-necko-wifi
diff --git a/extra/firefox-esr/sources b/extra/firefox-esr/sources
index 66634935..a2db6419 100644
--- a/extra/firefox-esr/sources
+++ b/extra/firefox-esr/sources
@@ -1,7 +1,6 @@
-https://ftp.mozilla.org/pub/firefox/releases/68.8.0esr/source/firefox-68.8.0esr.source.tar.xz
+https://ftp.mozilla.org/pub/firefox/releases/68.9.0esr/source/firefox-68.9.0esr.source.tar.xz
 https://ftp.gnu.org/gnu/autoconf/autoconf-2.13.tar.gz autoconf2.13/
 https://www.tortall.net/projects/yasm/releases/yasm-1.3.0.tar.gz yasm/
-files/mozconfig
 files/stab.h toolkit/crashreporter/google-breakpad/src/
 patches/fix-fortify-system-wrappers.patch
 patches/fix-seccomp-bpf.patch
diff --git a/extra/firefox-esr/version b/extra/firefox-esr/version
index 2fdceddf..fd4d532f 100644
--- a/extra/firefox-esr/version
+++ b/extra/firefox-esr/version
@@ -1 +1 @@
-68.8.0esr 1
+68.9.0esr 1