diff --git a/.gitignore b/.gitignore
index e1f3642..fa57a27 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,5 @@
 SOURCES/cbindgen-vendor.tar.xz
 SOURCES/nspr-4.32.0-1.el8_1.src.rpm
 SOURCES/nss-3.67.0-7.el8_1.src.rpm
-SOURCES/thunderbird-91.9.0.processed-source.tar.xz
-SOURCES/thunderbird-langpacks-91.9.0-20220503.tar.xz
+SOURCES/thunderbird-91.9.1.processed-source.tar.xz
+SOURCES/thunderbird-langpacks-91.9.1-20220523.tar.xz
diff --git a/.thunderbird.metadata b/.thunderbird.metadata
index 437aa41..97b8738 100644
--- a/.thunderbird.metadata
+++ b/.thunderbird.metadata
@@ -1,5 +1,5 @@
 c822547dbc12e2baebdfdfb38b665e23f0c2513a SOURCES/cbindgen-vendor.tar.xz
 b5fd1332d8e0d37339ae170c7bebcb63a40b22e0 SOURCES/nspr-4.32.0-1.el8_1.src.rpm
 8fff814901e03c2518ede2f8992d898f5ba61ed9 SOURCES/nss-3.67.0-7.el8_1.src.rpm
-e012b11182f73663668bd7f3ebe84acd6e51b44d SOURCES/thunderbird-91.9.0.processed-source.tar.xz
-7cc62140aef4a07dec14fcae4103f57e11859ec1 SOURCES/thunderbird-langpacks-91.9.0-20220503.tar.xz
+4a4c1c234f9e16c184726d8327f4788402e93b82 SOURCES/thunderbird-91.9.1.processed-source.tar.xz
+fb1e4275d84a8ef4f9b3ad82ef759f35e25034b5 SOURCES/thunderbird-langpacks-91.9.1-20220523.tar.xz
diff --git a/SPECS/thunderbird.spec b/SPECS/thunderbird.spec
index 69a0dd3..97e9847 100644
--- a/SPECS/thunderbird.spec
+++ b/SPECS/thunderbird.spec
@@ -126,10 +126,18 @@ end}
 
 %global official_branding       1
 %global build_langpacks         1
+
+# Workaround the dreaded "upstream source file changed content" rpmdiff failure that only secalert can waive.
+# If set to .b2 or .b3 ... the processed source file needs to be renamed before upload, e.g.
+# thunderbird-91.9.0.b2.processed-source.tar.xz
+# With does_not_exist it's empty and source file name as is.
+#global buildnum %{?does_not_exist}
+%global buildnum %{?does_not_exist}
+
 Summary:        Mozilla Thunderbird mail/newsgroup client
 Name:           thunderbird
-Version:        91.9.0
-Release:        3%{?dist}
+Version:        91.9.1
+Release:        1%{?dist}
 URL:            http://www.mozilla.org/projects/thunderbird/
 License:        MPLv1.1 or GPLv2+ or LGPLv2+
 Group:          Applications/Internet
@@ -153,9 +161,9 @@ ExcludeArch:    aarch64 s390 ppc
 # The official tarball has to be always processed by the process-official-tarball
 # script.
 # Link to official tarball: https://archive.mozilla.org/pub/thunderbird/releases/%%{version}%%{?pre_version}/source/thunderbird-%%{version}%%{?pre_version}.source.tar.xz
-Source0:        thunderbird-%{version}%{?pre_version}.processed-source.tar.xz
+Source0:        thunderbird-%{version}%{?pre_version}%{?buildnum}.processed-source.tar.xz
 %if %{build_langpacks}
-Source1:        thunderbird-langpacks-%{version}%{?ext_version}-20220503.tar.xz
+Source1:        thunderbird-langpacks-%{version}%{?ext_version}-20220523.tar.xz
 %endif
 Source2:        cbindgen-vendor.tar.xz
 Source3:        get-calendar-langpacks.sh
@@ -435,7 +443,7 @@ echo "use_rustts            %{?use_rustts}"
 %patch516 -p1 -b .expat-CVE-2022-25235
 %patch517 -p1 -b .expat-CVE-2022-25236
 %patch518 -p1 -b .expat-CVE-2022-25315
-#patch237 -p1 -b .disable-openpgp-in-thunderbird
+%patch237 -p1 -b .disable-openpgp-in-thunderbird
 
 
 %patch1001 -p1 -b .ppc64le-inline
@@ -1020,7 +1028,7 @@ rm -rf %{_prefix}/lib/debug/lib64/%{name}-devel-*
 
 
 # Removing librnp.so - we cannot deliver that in RHELs
-#{__rm} -rf %{buildroot}%{mozappdir}/librnp.so
+%{__rm} -rf %{buildroot}%{mozappdir}/librnp.so
 
 # Register as an application to be visible in the software center
 #
@@ -1124,9 +1132,12 @@ gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || :
 #===============================================================================
 
 %changelog
-* Thu May 05 2022 CentOS Sources <bugs@centos.org> - 91.9.0-3.el8.centos
+* Thu May 26 2022 CentOS Sources <bugs@centos.org> - 91.9.1-1.el8.centos
 - Apply debranding changes
 
+* Mon May 23 2022 Jan Horak <jhorak@redhat.com> - 91.9.1-1
+- Update to 91.9.1 build1
+
 * Tue May 03 2022 Eike Rathke <erack@redhat.com> - 91.9.0-3
 - Update to 91.9.0 build3