diff --git a/.gitignore b/.gitignore
index 3470aab..a6a5784 100644
--- a/.gitignore
+++ b/.gitignore
@@ -309,3 +309,5 @@ thunderbird-langpacks-3.1.2-20100803.tar.bz2
 /thunderbird-78.3.1.source.tar.xz
 /thunderbird-langpacks-78.3.1-20200930.tar.xz
 /cbindgen-vendor-0.14.3.tar.xz
+/thunderbird-78.4.0.source.tar.xz
+/thunderbird-langpacks-78.4.0-20201022.tar.xz
diff --git a/sources b/sources
index 7662177..cbc5c37 100644
--- a/sources
+++ b/sources
@@ -1,3 +1,2 @@
-SHA512 (thunderbird-78.3.1.source.tar.xz) = 16b05e51776ba16503bc5fba02a6d0b5050a206e264a4707544354ad76af61902fd2dcf5d97b82b432dc69362ccd18543a0acccd80e06648e6c6f470886da450
-SHA512 (thunderbird-langpacks-78.3.1-20200930.tar.xz) = 649ed59bdf7b988ca482b3bdb1dd2ea31741daeacc17c783f54e3fc65ac4ac17569d2cc54f357752bd0835914db5f59d638a781634d89a10acd3eee2acb9eb94
-SHA512 (cbindgen-vendor-0.14.3.tar.xz) = 33c8d28547674121f690eea0d3ebac33926a39caacac787bf8ed8b346478822e74da5a4a1f57ab4df4105fa8376739a2ece888845a85bc5712aaed20e4a508bc
+SHA512 (thunderbird-78.4.0.source.tar.xz) = 0536a59286dec2f05e3fa00bdcc4f2e52139d9c53d5c086e0074d0d7c6a3b01bbb4beee2c996ffecace2950d1b8b35e2731e6c681ece804b1505acd26f58b308
+SHA512 (thunderbird-langpacks-78.4.0-20201022.tar.xz) = 4430e33dce1404941aad3122f755bfb540fba8fb4ea4a2b4f1f6e564375b8663bf1f341183527fd598f79fb7500c71219aea21e44484ee5dd891cd510750ec70
diff --git a/thunderbird-redhat-default-prefs.js b/thunderbird-redhat-default-prefs.js
index bca1328..db95fec 100644
--- a/thunderbird-redhat-default-prefs.js
+++ b/thunderbird-redhat-default-prefs.js
@@ -30,4 +30,6 @@ pref("network.negotiate-auth.allow-insecure-ntlm-v1", true);
 pref("security.use_mozillapkix_verification", false);
 /* Use OS settings for UI language */
 pref("intl.locale.requested", "");
+/* Disable telemetry */
+pref("datareporting.healthreport.uploadEnabled", false);
 
diff --git a/thunderbird.spec b/thunderbird.spec
index ecf7ec1..e8de2c4 100644
--- a/thunderbird.spec
+++ b/thunderbird.spec
@@ -83,13 +83,13 @@ ExcludeArch: armv7hl
 
 Summary:        Mozilla Thunderbird mail/newsgroup client
 Name:           thunderbird
-Version:        78.3.1
-Release:        2%{?dist}
+Version:        78.4.0
+Release:        1%{?dist}
 URL:            http://www.mozilla.org/projects/thunderbird/
 License:        MPLv1.1 or GPLv2+ or LGPLv2+
 Source0:        ftp://ftp.mozilla.org/pub/thunderbird/releases/%{version}%{?pre_version}/source/thunderbird-%{version}%{?pre_version}.source.tar.xz
 %if %{build_langpacks}
-Source1:        thunderbird-langpacks-%{version}-20200930.tar.xz
+Source1:        thunderbird-langpacks-%{version}-20201022.tar.xz
 %endif
 Source3:        get-calendar-langpacks.sh
 Source4:        cbindgen-vendor-0.14.3.tar.xz
@@ -725,6 +725,9 @@ gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || :
 #===============================================================================
 
 %changelog
+* Thu Oct 22 2020 Jan Horak <jhorak@redhat.com> - 78.4.0-1
+- Update to 78.4.0 build1
+
 * Wed Oct 07 2020 Jan Horak <jhorak@redhat.com> - 78.3.1-2
 - Reenable s390x