--- a/mail/base/content/aboutDialog.xul
+++ b/mail/base/content/aboutDialog.xul
@@ -36,17 +36,23 @@
   <script type="application/javascript" src="chrome://messenger/content/specialTabs.js"/>
   <!-- This one is for openURL -->
   <script type="application/javascript" src="chrome://global/content/contentAreaUtils.js"/>
 
   <vbox id="aboutDialogContainer">
     <hbox id="clientBox">
       <vbox id="leftBox" flex="1"/>
       <vbox id="rightBox" flex="1">
-#expand <label id="version">__MOZ_APP_VERSION__</label>
+        <hbox align="baseline">
+#expand <label id="version">__MOZ_APP_VERSION_DISPLAY__</label>
+#ifndef NIGHTLY_BUILD
+#expand <label id="releasenotes" class="text-link" href="https://www.mozilla.org/thunderbird/__MOZ_APP_VERSION__/releasenotes/">&releaseNotes.link;</label>
+#endif
+        </hbox>
+
         <label id="distribution" class="text-blurb"/>
         <label id="distributionId" class="text-blurb"/>
 
         <vbox id="detailsBox">
           <vbox id="updateBox">
 #ifdef MOZ_UPDATER
             <deck id="updateDeck" orient="vertical">
               <hbox id="checkForUpdates" align="center">

--- a/mail/base/moz.build
+++ b/mail/base/moz.build
@@ -6,16 +6,17 @@
 DIRS += ['modules']
 
 TEST_DIRS += ['test']
 
 JAR_MANIFESTS += ['jar.mn']
 
 DEFINES['PRE_RELEASE_SUFFIX'] = ''
 DEFINES['MOZ_APP_VERSION'] = CONFIG['MOZ_APP_VERSION']
+DEFINES['MOZ_APP_VERSION_DISPLAY'] = CONFIG['MOZ_APP_VERSION_DISPLAY']
 DEFINES['APP_LICENSE_BLOCK'] = '%s/content/overrides/app-license.html' % SRCDIR
 
 if CONFIG['MOZILLA_OFFICIAL']:
     DEFINES['OFFICIAL_BUILD'] = 1
 
 if CONFIG['MOZ_WIDGET_TOOLKIT'] in ('windows', 'gtk2', 'gtk3', 'cocoa'):
     DEFINES['HAVE_SHELL_SERVICE'] = 1
 

new file mode 100644
--- /dev/null
+++ b/mail/config/version_display.txt
@@ -0,0 +1,1 @@
+50.0a1

--- a/mail/confvars.sh
+++ b/mail/confvars.sh
@@ -20,16 +20,18 @@ if test "$OS_ARCH" = "WINNT"; then
   fi
 fi
 
 MOZ_SAFE_BROWSING=1
 MOZ_MORK=1
 
 MOZ_APP_VERSION_TXT=${_topsrcdir}/$MOZ_BUILD_APP/config/version.txt
 MOZ_APP_VERSION=`cat $MOZ_APP_VERSION_TXT`
+MOZ_APP_VERSION_DISPLAY_TXT=${_topsrcdir}/$MOZ_BUILD_APP/config/version_display.txt
+MOZ_APP_VERSION_DISPLAY=`cat $MOZ_APP_VERSION_DISPLAY_TXT`
 THUNDERBIRD_VERSION=$MOZ_APP_VERSION
 
 MOZ_UA_BUILDID=20100101
 
 MOZ_BRANDING_DIRECTORY=mail/branding/nightly
 MOZ_OFFICIAL_BRANDING_DIRECTORY=other-licenses/branding/thunderbird
 MOZ_APP_ID={3550f703-e582-4d05-9a08-453d09bdfdc6}
 # This should usually be the same as the value MAR_CHANNEL_ID.

--- a/mail/locales/en-US/chrome/messenger/aboutDialog.dtd
+++ b/mail/locales/en-US/chrome/messenger/aboutDialog.dtd
@@ -39,16 +39,18 @@
 <!ENTITY helpus.start               "Want to help? ">
 <!-- LOCALIZATION NOTE (helpus.donateLink): This is a link title that links to the thunderbird donation page -->
 <!ENTITY helpus.donateLink          "Make a donation">
 <!ENTITY helpus.middle              " or ">
 <!-- LOCALIZATION NOTE (helpus.getInvolvedLink): This is a link title that links to http://www.mozilla.org/contribute/. -->
 <!ENTITY helpus.getInvolvedLink     "get involved!">
 <!ENTITY helpus.end                 "">
 
+<!ENTITY releaseNotes.link          "Release notes">
+
 <!-- LOCALIZATION NOTE (bottomLinks.license): This is a link title that links to about:license. -->
 <!ENTITY bottomLinks.license        "Licensing Information">
 
 <!-- LOCALIZATION NOTE (bottomLinks.rights): This is a link title that links to about:rights. -->
 <!ENTITY bottomLinks.rights         "End-User Rights">
 
 <!-- LOCALIZATION NOTE (bottomLinks.privacy): This is a link title that links to https://www.mozilla.org/legal/privacy/. -->
 <!ENTITY bottomLinks.privacy        "Privacy Policy">