diff --git a/.gitignore b/.gitignore
index 7ebea59..ebb6a59 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,10 +2,10 @@ SOURCES/Python-2.7.13.tar.xz
 SOURCES/cbindgen-vendor-0.14.3.tar.xz
 SOURCES/gtk3-private-3.22.26-1.el6.src.rpm
 SOURCES/libffi-3.0.13-18.el7_3.src.rpm
-SOURCES/nodejs-10.21.0-5.fc32.src.rpm
+SOURCES/nodejs-10.21.0-4.fc32.src.rpm
 SOURCES/nspr-4.25.0-1.el8_0.src.rpm
 SOURCES/nss-3.53.1-3.fc32.src.rpm
 SOURCES/openssl-1.0.2k-19.6.bundle.el7_7.src.rpm
-SOURCES/thunderbird-78.3.1.source.tar.xz
-SOURCES/thunderbird-langpacks-78.3.1-20200929.tar.xz
+SOURCES/thunderbird-78.3.0.source.tar.xz
+SOURCES/thunderbird-langpacks-78.3.0-20200919.tar.xz
 SOURCES/yasm-1.2.0-3.el5.src.rpm
diff --git a/.thunderbird.metadata b/.thunderbird.metadata
index c09d16c..929324d 100644
--- a/.thunderbird.metadata
+++ b/.thunderbird.metadata
@@ -2,10 +2,10 @@
 a9effcc06cf80eaa22f12c1f7d6aa4266a1c4966 SOURCES/cbindgen-vendor-0.14.3.tar.xz
 0de63f863b158454b9429234b52ed28a397ec45c SOURCES/gtk3-private-3.22.26-1.el6.src.rpm
 e188ab1a444697bc649e223c28389d82ca94c472 SOURCES/libffi-3.0.13-18.el7_3.src.rpm
-5715f987bc0024ce5d72993cb101b8268350033b SOURCES/nodejs-10.21.0-5.fc32.src.rpm
+5715f987bc0024ce5d72993cb101b8268350033b SOURCES/nodejs-10.21.0-4.fc32.src.rpm
 07d67c90367c3ec0d6cebc1a5793c21076d34b78 SOURCES/nspr-4.25.0-1.el8_0.src.rpm
 223c02166b1cb9863b9f453ef687d7805a93e7af SOURCES/nss-3.53.1-3.fc32.src.rpm
 a379070abf5000cde61411c97af7e733b267a4d3 SOURCES/openssl-1.0.2k-19.6.bundle.el7_7.src.rpm
-aac14b96dd577ba26504ac0ab5d77fc9a85cede3 SOURCES/thunderbird-78.3.1.source.tar.xz
-286e1da1db164234bf0173ed2a8ee0b5e53a2f11 SOURCES/thunderbird-langpacks-78.3.1-20200929.tar.xz
+6f7d458199f44627b38a8b5f841f6f9b39c6303a SOURCES/thunderbird-78.3.0.source.tar.xz
+d9888ce2477f6a9ff10b0411bd4b372d01563a31 SOURCES/thunderbird-langpacks-78.3.0-20200919.tar.xz
 77fd30f7ebc12a629a31c1e252cec06af55a71fe SOURCES/yasm-1.2.0-3.el5.src.rpm
diff --git a/SOURCES/Bug-1238661---fix-mozillaSignalTrampoline-to-work-.patch b/SOURCES/Bug-1238661---fix-mozillaSignalTrampoline-to-work-.patch
deleted file mode 100644
index 6dfe2ad..0000000
--- a/SOURCES/Bug-1238661---fix-mozillaSignalTrampoline-to-work-.patch
+++ /dev/null
@@ -1,12 +0,0 @@
-diff -up firefox-60.0/mfbt/LinuxSignal.h.mozilla-1238661 firefox-60.0/mfbt/LinuxSignal.h
---- firefox-60.0/mfbt/LinuxSignal.h.mozilla-1238661	2018-04-27 08:55:38.848241768 +0200
-+++ firefox-60.0/mfbt/LinuxSignal.h	2018-04-27 09:06:47.946769859 +0200
-@@ -22,7 +22,7 @@ __attribute__((naked)) void SignalTrampo
-                                              void* aContext) {
-   asm volatile("nop; nop; nop; nop" : : : "memory");
- 
--  asm volatile("b %0" : : "X"(H) : "memory");
-+  asm volatile("bx %0" : : "r"(H), "l"(aSignal), "l"(aInfo), "l"(aContext) : "memory");
- }
- 
- #  define MOZ_SIGNAL_TRAMPOLINE(h) (mozilla::SignalTrampoline<h>)
diff --git a/SOURCES/Bug-1526653---fix_user_vfp_armv7.patch b/SOURCES/Bug-1526653---fix_user_vfp_armv7.patch
deleted file mode 100644
index 3f84f95..0000000
--- a/SOURCES/Bug-1526653---fix_user_vfp_armv7.patch
+++ /dev/null
@@ -1,35 +0,0 @@
-From fd6847c9416f9eebde636e21d794d25d1be8791d Mon Sep 17 00:00:00 2001
-From: Mike Hommey <mh@glandium.org>
-Date: Sat, 1 Jun 2019 09:06:01 +0900
-Subject: [PATCH] Bug 1526653 - Include struct definitions for user_vfp and
- user_vfp_exc.
-
----
- js/src/wasm/WasmSignalHandlers.cpp | 11 ++++++++++-
- 1 file changed, 10 insertions(+), 1 deletion(-)
-
-diff --git a/js/src/wasm/WasmSignalHandlers.cpp b/js/src/wasm/WasmSignalHandlers.cpp
-index 636537f8478..383c380f04c 100644
---- a/js/src/wasm/WasmSignalHandlers.cpp
-+++ b/js/src/wasm/WasmSignalHandlers.cpp
-@@ -248,7 +248,16 @@ using mozilla::DebugOnly;
- #endif
- 
- #ifdef WASM_EMULATE_ARM_UNALIGNED_FP_ACCESS
--#  include <sys/user.h>
-+struct user_vfp {
-+  unsigned long long fpregs[32];
-+  unsigned long fpscr;
-+};
-+
-+struct user_vfp_exc {
-+  unsigned long fpexc;
-+  unsigned long fpinst;
-+  unsigned long fpinst2;
-+};
- #endif
- 
- #if defined(ANDROID)
--- 
-2.20.1
-
diff --git a/SOURCES/rhel6-auxv.patch b/SOURCES/rhel6-auxv.patch
deleted file mode 100644
index e7b81cd..0000000
--- a/SOURCES/rhel6-auxv.patch
+++ /dev/null
@@ -1,21 +0,0 @@
-diff -up thunderbird-78.3.0/comm/third_party/botan/src/lib/utils/os_utils.cpp.auxv thunderbird-78.3.0/comm/third_party/botan/src/lib/utils/os_utils.cpp
---- thunderbird-78.3.0/comm/third_party/botan/src/lib/utils/os_utils.cpp.auxv	2020-09-25 17:23:50.810638756 +0200
-+++ thunderbird-78.3.0/comm/third_party/botan/src/lib/utils/os_utils.cpp	2020-09-25 17:26:00.156999592 +0200
-@@ -42,7 +42,7 @@
- 
- #if defined(BOTAN_TARGET_OS_HAS_GETAUXVAL) || defined(BOTAN_TARGET_OS_IS_ANDROID) || \
-   defined(BOTAN_TARGET_OS_HAS_ELF_AUX_INFO)
--  #include <sys/auxv.h>
-+  //#include <sys/auxv.h>
- #endif
- 
- #if defined(BOTAN_TARGET_OS_HAS_WIN32)
-@@ -109,7 +109,7 @@ uint32_t OS::get_process_id()
- unsigned long OS::get_auxval(unsigned long id)
-    {
- #if defined(BOTAN_TARGET_OS_HAS_GETAUXVAL)
--   return ::getauxval(id);
-+   //return ::getauxval(id);
- #elif defined(BOTAN_TARGET_OS_IS_ANDROID) && defined(BOTAN_TARGET_ARCH_IS_ARM32)
- 
-    if(id == 0)
diff --git a/SOURCES/thunderbird-centos-default-prefs.js.el6 b/SOURCES/thunderbird-centos-default-prefs.js.el6
deleted file mode 100644
index 75de82e..0000000
--- a/SOURCES/thunderbird-centos-default-prefs.js.el6
+++ /dev/null
@@ -1,30 +0,0 @@
-pref("app.update.enabled", false);
-pref("app.update.autoInstallEnabled", false);
-# Allow users to set custom colors
-# pref("browser.display.use_system_colors",   true);
-pref("general.useragent.vendor", "CentOS");
-pref("general.useragent.vendorSub", "THUNDERBIRD_RPM_VR");
-pref("intl.locale.matchOS", true);
-pref("mail.shell.checkDefaultClient", false);
-pref("toolkit.networkmanager.disable", false);
-pref("offline.autoDetect", true);
-
-# Disable global indexing by default
-pref("mailnews.database.global.indexer.enabled", false);
-
-# Do not switch to Smart Folders after upgrade to 3.0b4
-pref("mail.folder.views.version", "1");
-pref("extensions.shownSelectionUI", true);
-pref("extensions.autoDisableScope", 0);
-
-# For rhbz#1024232
-pref("ui.SpellCheckerUnderlineStyle",       1);
-
-/* Workaround for rhbz#1134876 */
-pref("javascript.options.baselinejit",      false);
-/* Workaround for rhbz#1110291 */
-pref("network.negotiate-auth.allow-insecure-ntlm-v1", true);
-/* Workaround for mozbz#1063315 */
-pref("security.use_mozillapkix_verification", false);
-/* Use OS settings for UI language */
-pref("intl.locale.requested", "");
diff --git a/SOURCES/thunderbird-centos-default-prefs.js.el7 b/SOURCES/thunderbird-centos-default-prefs.js.el7
deleted file mode 100644
index 75de82e..0000000
--- a/SOURCES/thunderbird-centos-default-prefs.js.el7
+++ /dev/null
@@ -1,30 +0,0 @@
-pref("app.update.enabled", false);
-pref("app.update.autoInstallEnabled", false);
-# Allow users to set custom colors
-# pref("browser.display.use_system_colors",   true);
-pref("general.useragent.vendor", "CentOS");
-pref("general.useragent.vendorSub", "THUNDERBIRD_RPM_VR");
-pref("intl.locale.matchOS", true);
-pref("mail.shell.checkDefaultClient", false);
-pref("toolkit.networkmanager.disable", false);
-pref("offline.autoDetect", true);
-
-# Disable global indexing by default
-pref("mailnews.database.global.indexer.enabled", false);
-
-# Do not switch to Smart Folders after upgrade to 3.0b4
-pref("mail.folder.views.version", "1");
-pref("extensions.shownSelectionUI", true);
-pref("extensions.autoDisableScope", 0);
-
-# For rhbz#1024232
-pref("ui.SpellCheckerUnderlineStyle",       1);
-
-/* Workaround for rhbz#1134876 */
-pref("javascript.options.baselinejit",      false);
-/* Workaround for rhbz#1110291 */
-pref("network.negotiate-auth.allow-insecure-ntlm-v1", true);
-/* Workaround for mozbz#1063315 */
-pref("security.use_mozillapkix_verification", false);
-/* Use OS settings for UI language */
-pref("intl.locale.requested", "");
diff --git a/SOURCES/thunderbird-redhat-default-prefs.js.rhel6 b/SOURCES/thunderbird-redhat-default-prefs.js.rhel6
new file mode 100644
index 0000000..c412cb5
--- /dev/null
+++ b/SOURCES/thunderbird-redhat-default-prefs.js.rhel6
@@ -0,0 +1,30 @@
+pref("app.update.enabled", false);
+pref("app.update.autoInstallEnabled", false);
+# Allow users to set custom colors
+# pref("browser.display.use_system_colors",   true);
+pref("general.useragent.vendor", "Red Hat");
+pref("general.useragent.vendorSub", "THUNDERBIRD_RPM_VR");
+pref("intl.locale.matchOS", true);
+pref("mail.shell.checkDefaultClient", false);
+pref("toolkit.networkmanager.disable", false);
+pref("offline.autoDetect", true);
+
+# Disable global indexing by default
+pref("mailnews.database.global.indexer.enabled", false);
+
+# Do not switch to Smart Folders after upgrade to 3.0b4
+pref("mail.folder.views.version", "1");
+pref("extensions.shownSelectionUI", true);
+pref("extensions.autoDisableScope", 0);
+
+# For rhbz#1024232
+pref("ui.SpellCheckerUnderlineStyle",       1);
+
+/* Workaround for rhbz#1134876 */
+pref("javascript.options.baselinejit",      false);
+/* Workaround for rhbz#1110291 */
+pref("network.negotiate-auth.allow-insecure-ntlm-v1", true);
+/* Workaround for mozbz#1063315 */
+pref("security.use_mozillapkix_verification", false);
+/* Use OS settings for UI language */
+pref("intl.locale.requested", "");
diff --git a/SOURCES/thunderbird-redhat-default-prefs.js.rhel7 b/SOURCES/thunderbird-redhat-default-prefs.js.rhel7
new file mode 100644
index 0000000..c412cb5
--- /dev/null
+++ b/SOURCES/thunderbird-redhat-default-prefs.js.rhel7
@@ -0,0 +1,30 @@
+pref("app.update.enabled", false);
+pref("app.update.autoInstallEnabled", false);
+# Allow users to set custom colors
+# pref("browser.display.use_system_colors",   true);
+pref("general.useragent.vendor", "Red Hat");
+pref("general.useragent.vendorSub", "THUNDERBIRD_RPM_VR");
+pref("intl.locale.matchOS", true);
+pref("mail.shell.checkDefaultClient", false);
+pref("toolkit.networkmanager.disable", false);
+pref("offline.autoDetect", true);
+
+# Disable global indexing by default
+pref("mailnews.database.global.indexer.enabled", false);
+
+# Do not switch to Smart Folders after upgrade to 3.0b4
+pref("mail.folder.views.version", "1");
+pref("extensions.shownSelectionUI", true);
+pref("extensions.autoDisableScope", 0);
+
+# For rhbz#1024232
+pref("ui.SpellCheckerUnderlineStyle",       1);
+
+/* Workaround for rhbz#1134876 */
+pref("javascript.options.baselinejit",      false);
+/* Workaround for rhbz#1110291 */
+pref("network.negotiate-auth.allow-insecure-ntlm-v1", true);
+/* Workaround for mozbz#1063315 */
+pref("security.use_mozillapkix_verification", false);
+/* Use OS settings for UI language */
+pref("intl.locale.requested", "");
diff --git a/SPECS/thunderbird.spec b/SPECS/thunderbird.spec
index 8d0499f..f80bb08 100644
--- a/SPECS/thunderbird.spec
+++ b/SPECS/thunderbird.spec
@@ -1,7 +1,3 @@
-%ifarch %{arm}
-%undefine _debugsource_packages
-%endif
-
 # Set for local builds only
 %global disable_toolsets  0
 
@@ -195,8 +191,8 @@
 %global build_langpacks         1
 Summary:        Mozilla Thunderbird mail/newsgroup client
 Name:           thunderbird
-Version:        78.3.1
-Release:        1%{?dist}
+Version:        78.3.0
+Release:        3%{?dist}
 URL:            http://www.mozilla.org/projects/thunderbird/
 License:        MPLv1.1 or GPLv2+ or LGPLv2+
 Group:          Applications/Internet
@@ -211,7 +207,7 @@ ExclusiveArch:  i686 x86_64 ppc64 s390x
 # From ftp://archive.mozilla.org/pub/thunderbird/releases/%{version}%{?ext_version}/source
 Source0:        https://archive.mozilla.org/pub/thunderbird/releases/%{version}%{?pre_version}/source/thunderbird-%{version}%{?pre_version}.source.tar.xz
 %if %{build_langpacks}
-Source1:        thunderbird-langpacks-%{version}%{?ext_version}-20200929.tar.xz
+Source1:        thunderbird-langpacks-%{version}%{?ext_version}-20200919.tar.xz
 # Locales for lightning
 %endif
 Source2:        cbindgen-vendor-0.14.3.tar.xz
@@ -233,10 +229,10 @@ Source205:      gtk3-private-%{gtk3_nvr}-setup-flags-env.inc
 Source206:      gtk3-private-%{gtk3_nvr}-requires-provides-filter.inc
 Source301:      yasm-1.2.0-3.el5.src.rpm
 Source303:      libffi-3.0.13-18.el7_3.src.rpm
-Source304:      nodejs-10.21.0-5.fc32.src.rpm
+Source304:      nodejs-10.21.0-4.fc32.src.rpm
 Source305:      openssl-1.0.2k-19.6.bundle.el7_7.src.rpm
-Source601:      thunderbird-centos-default-prefs.js.el6
-Source701:      thunderbird-centos-default-prefs.js.el7
+Source601:      thunderbird-redhat-default-prefs.js.rhel6
+Source701:      thunderbird-redhat-default-prefs.js.rhel7
 
 ## Firefox patches
 
@@ -306,7 +302,6 @@ Patch602:        rhel6-mach-fail.patch
 Patch603:        rhel6-zconst.patch
 Patch604:        rhel6-auxvh.patch
 Patch605:        rhel6-abiv2-mozbz1642174.patch
-Patch606:        rhel6-auxv.patch
 
 %if %{?system_nss}
 %if !0%{?bundle_nss}
@@ -610,7 +605,6 @@ echo "use_bundled_yasm      %{?use_bundled_yasm}"
 %patch603 -p1 -b .rhel6-zconst
 %patch604 -p1 -b .rhel6-auxvh
 %patch605 -p1 -b .rhel6-abiv2-mozbz1642174
-%patch606 -p1 -b .rhel6-auxv
 %endif
 
 # CentOS patches
@@ -669,7 +663,7 @@ echo "ac_add_options --enable-system-hunspell" >> .mozconfig
 %endif
 %ifarch armv7hl
 # ARMv7 need that (rhbz#1426850)
-%global optimize_flags "-g0 -O2 -fno-schedule-insns -fno-lto"
+%global optimize_flags "-g -O2 -fno-schedule-insns"
 %endif
 %ifarch ppc64le aarch64
 %global optimize_flags "-g -O2"
@@ -1049,10 +1043,6 @@ MOZ_OPT_FLAGS=$(echo "$MOZ_OPT_FLAGS" | %{__sed} -e 's/-g/-g1/')
 # (OOM when linking, rhbz#1238225)
 export MOZ_DEBUG_FLAGS=" "
 %endif
-%ifarch %{arm}
-MOZ_OPT_FLAGS=$(echo "$MOZ_OPT_FLAGS" | %{__sed} -e 's/-g/-g0/')
-export MOZ_DEBUG_FLAGS=" "
-%endif
 
 # We don't wantfirefox to use CK_GCM_PARAMS_V3 in nss
 MOZ_OPT_FLAGS="$MOZ_OPT_FLAGS -DNSS_PKCS11_3_0_STRICT"
@@ -1092,6 +1082,7 @@ MOZ_SMP_FLAGS=-j1
 [ "$RPM_BUILD_NCPUS" -ge 8 ] && MOZ_SMP_FLAGS=-j2
 %endif
 %endif
+#FIXME workaround for oom
 
 cat /proc/meminfo
 # Free memory in kB
@@ -1109,12 +1100,6 @@ CPU_AVAILABLE=$(/usr/bin/getconf _NPROCESSORS_ONLN)
 # gtk3-private-setup-flags-env.inc
 %include_file %{SOURCE205}
 %endif
-#FIXME workaround for oom
-
-cat /proc/meminfo
-# Free memory in kB
-
-MEM_AVAILABLE=$(grep MemAvailable /proc/meminfo | awk '{ print $2 }')
 
 %if 0%{?bundle_nss}
 echo "Setting nss flags"
@@ -1428,12 +1413,6 @@ gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || :
 #===============================================================================
 
 %changelog
-* Thu Oct 01 2020 CentOS Sources <bugs@centos.org> - 78.3.1-1.el8.centos
-- Apply debranding changes
-
-* Tue Sep 29 2020 Jan Horak <jhorak@redhat.com> - 78.3.1-1
-- Update to 78.3.1 build1
-
 * Sat Sep 19 2020 Jan Horak <jhorak@redhat.com> - 78.3.0-3
 - Update to 78.3.0 build1
 - Remove librdp.so as long as we cannot ship it in RHEL