diff --git a/.gitignore b/.gitignore
index 68fdc3a..d6aadd8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -281,3 +281,6 @@
 /firefox-langpacks-91.2.0esr-20210929.tar.xz
 /firefox-91.3.0esr.processed-source.tar.xz
 /firefox-langpacks-91.3.0esr-20211101.tar.xz
+/firefox-91.4.0esr.processed-source.tar.xz
+/firefox-langpacks-91.4.0esr-20211201.tar.xz
+/nss-3.67.0-7.el8_1.src.rpm
diff --git a/firefox.spec b/firefox.spec
index 562f7e4..84da496 100644
--- a/firefox.spec
+++ b/firefox.spec
@@ -128,7 +128,7 @@ end}
 
 Summary:        Mozilla Firefox Web browser
 Name:           firefox
-Version:        91.3.0
+Version:        91.4.0
 Release:        1%{?dist}
 URL:            https://www.mozilla.org/firefox/
 License:        MPLv1.1 or GPLv2+ or LGPLv2+
@@ -149,7 +149,7 @@ ExcludeArch:    s390 ppc
 # Link to official tarball: https://hg.mozilla.org/releases/mozilla-release/archive/firefox-%%{version}%%{?pre_version}.source.tar.xz
 Source0:        firefox-%{version}%{?pre_version}.processed-source.tar.xz
 %if %{build_langpacks}
-Source1:        firefox-langpacks-%{version}%{?pre_version}-20211101.tar.xz
+Source1:        firefox-langpacks-%{version}%{?pre_version}-20211201.tar.xz
 %endif
 Source2:        cbindgen-vendor.tar.xz
 Source3:        process-official-tarball
@@ -168,7 +168,7 @@ Source26:       distribution.ini
 Source27:       google-api-key
 Source28:       node-stdout-nonblocking-wrapper
 
-Source403:      nss-3.67.0-6.el8_1.src.rpm
+Source403:      nss-3.67.0-7.el8_1.src.rpm
 Source401:      nss-setup-flags-env.inc
 Source402:      nspr-4.32.0-1.el8_1.src.rpm
 
@@ -1247,6 +1247,9 @@ gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || :
 #---------------------------------------------------------------------
 
 %changelog
+* Wed Dec 01 2021 Eike Rathke <erack@redhat.com> - 91.4.0-1
+- Update to 91.4.0 build1
+
 * Mon Nov 01 2021 Eike Rathke <erack@redhat.com> - 91.3.0-1
 - Update to 91.3.0 build1
 
diff --git a/sources b/sources
index 71d6ed0..254e4e8 100644
--- a/sources
+++ b/sources
@@ -1,5 +1,5 @@
-SHA512 (nss-3.67.0-6.el8_1.src.rpm) = 6697fef5517c8c1d8c881243d60e35494fb6c11537467a38ce281d49fade5780764e81f5c044fe11dd020bc6c5655b77e65105c677a7812718cbc42061b3b5da
 SHA512 (cbindgen-vendor.tar.xz) = 9cb4a590584c53386a14deb1f1faf7b67ff8f312eff4a8dccab710738183c504387d69fa660021b495ed61603f4df1db689f35234c61e2e886962e40aab20c95
+SHA512 (nss-3.67.0-7.el8_1.src.rpm) = 15361c596fc4f2e4afc7d40d48c37886cad93849821d2bcad8213f34035a6951be127b436b6799083f2b4adb18a68870dbe273177d2d670eda9cc9680e6d6f63
 SHA512 (nspr-4.32.0-1.el8_1.src.rpm) = c181a19bc24aeb62aed1745a6a43ae8aa2ee0d903aa16cb6ec7d385286e60f6426049cc9669459434377a215f329502ffe6fc48a1edc52d5b3283ebc259e9dca
-SHA512 (firefox-91.3.0esr.processed-source.tar.xz) = c57a8cf3203029a469c3b9043cd58179601f6182d9a913f567de5129d70b3319c1c6a24ac000b6403011fe64d3bb168796f771447d4b7e7209de692babcc198d
-SHA512 (firefox-langpacks-91.3.0esr-20211101.tar.xz) = 65f2578e3e1661087c4549f7b1ff19ed55f89dc0c5f08dc28d46c6fbbf463ac57f7dff212a91d81b8efe72635c19477acff66235026588eba2004a70d1479467
+SHA512 (firefox-91.4.0esr.processed-source.tar.xz) = 2b90ca7bef38baf54919a6838bb668c229357dbb2180aad5f709c126d85b353448358712e1c968df5f0131838ec887b33e302c57d13f18d11ba48f497eb79bf2
+SHA512 (firefox-langpacks-91.4.0esr-20211201.tar.xz) = d03190d585d5195f6ed17b0fd4e993ac375956961bba63f11621936341b2c36e543ee679a96cfb71fb0e8a508549326e279b6ea8edac9bae8fe3371cdf314ac7