diff --git a/thunderbird.spec b/thunderbird.spec
index 2481e1f..e0bff52 100644
--- a/thunderbird.spec
+++ b/thunderbird.spec
@@ -10,7 +10,7 @@
 
 Name:          thunderbird
 Version:       60.5.0
-Release:       1mamba
+Release:       2mamba
 Summary:       Mozilla Thunderbird email, RSS, and newsgroup client
 Group:         Graphical Desktop/Applications/Internet
 Vendor:        openmamba
@@ -142,7 +142,7 @@ Because the project is small and tightly managed, bugs targeted to a particular
 This package contains static libraries and header files need for development.
 
 %prep
-%setup -q
+%setup -q -c -a0
 #-D -T
 #:<< ___EOF
 %define _use_internal_dependency_generator 0
@@ -197,6 +197,7 @@ chmod +x %{_builddir}/thunderbird-%{version}/find_requires.sh
 #  sed -i 's|python2.6 python2.5 python2.4 python|python2.6|' $c
 #done
 
+cd %{name}-%{version}
 rm -f .mozconfig
 cat << EOF > .mozconfig
 ac_add_options --enable-application=comm/mail
@@ -253,6 +254,8 @@ echo "export MOZ_DEBUG_SYMBOLS="1"" >> .mozconfig
 
 %build
 #:<< ___EOF
+cd %{name}-%{version}
+
 ## Disable C++ exceptions since Mozilla code is not exception-safe
 #MOZ_OPT_FLAGS=$(echo "$RPM_OPT_FLAGS" | \
 #              %{__sed} -e 's/-O2/-Os/' -e 's/-Wall//' -e 's/-fexceptions/-fno-exceptions/g')
@@ -287,6 +290,7 @@ export MOZILLA_OFFICIAL=1
 
 %install
 [ "%{buildroot}" != / ] && rm -rf "%{buildroot}"
+cd %{name}-%{version}
 export DESTDIR=%{buildroot}
 ./mach install
 #DESTDIR=%{buildroot} make -f client.mk install MOZ_SERVICES_SYNC="1"
@@ -303,16 +307,13 @@ install -D -m644 comm/mail/branding/thunderbird/TB-symbolic.svg \
     %{buildroot}%{_datadir}/icons/hicolor/symbolic/apps/thunderbird-symbolic.svg
 
 # FIXME handle system/user preferences with xdg-open
-for d in %{buildroot}%{tbdir}/greprefs %{buildroot}%{tbdir}/defaults/pref ; do
-mkdir -p $d
-cat > $d/all-redhat.js << _EOF
+cat > %{buildroot}%{tbdir}/defaults/pref/vendor.js << _EOF
 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", "openmamba");
 pref("general.useragent.vendorSub", "%{version}-%{release}");
-pref("intl.locale.matchOS", true);
 pref("mail.shell.checkDefaultClient", false);
 pref("toolkit.networkmanager.disable", false);
 pref("network.protocol-handler.app.http", "%{_bindir}/firefox");
@@ -325,8 +326,16 @@ pref("mail.folder.views.version", "1");
 pref("network.protocol-handler.warn-external.ftp", true);
 pref("network.protocol-handler.warn-external.http", true);
 pref("network.protocol-handler.warn-external.https", true);
+# Use LANG environment variable to choose locale
+pref("intl.locale.requested", "");
+# Use system-provided dictionaries
+pref("spellchecker.dictionary_path", "%{_datadir}/myspell");
+# Disable default mailer checking.
+pref("mail.shell.checkDefaultMail", false);
+# Don't disable our bundled extensions in the application directory
+pref("extensions.autoDisableScopes", 11);
+pref("extensions.shownSelectionUI", true);
 _EOF
-done
 
 #rm -rf %{buildroot}%{_bindir}/thunderbird
 #rm -rf %{buildroot}%{_bindir}/thunderbird-config
@@ -446,7 +455,6 @@ fi
 #%{tbdir}/icons/updater.png
 %dir %{tbdir}/fonts
 %{tbdir}/fonts/EmojiOneMozilla.ttf
-%{tbdir}/greprefs/all-redhat.js
 %{tbdir}/gtk2/libmozgtk.so
 %dir %{tbdir}/isp
 %{tbdir}/isp/*
@@ -1261,6 +1269,9 @@ Chinese (Traditional) language support for Thunderbird.
 %{tbdir}/extensions/langpack-zh-TW@thunderbird.mozilla.org/
 
 %changelog
+* Fri Feb 08 2019 Silvan Calarco <silvan.calarco@mambasoft.it> 60.5.0-2mamba
+- update vendor.js to endable system default language support
+
 * Tue Feb 05 2019 Automatic Build System <autodist@mambasoft.it> 60.5.0-1mamba
 - automatic version update by autodist