--- a/calendar/lightning/install.rdf
+++ b/calendar/lightning/install.rdf
@@ -1,45 +1,1 @@
-<?xml version="1.0"?>
-<!-- This Source Code Form is subject to the terms of the Mozilla Public
-   - License, v. 2.0. If a copy of the MPL was not distributed with this
-   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
-
-
-#filter substitution
-<RDF xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
-     xmlns:em="http://www.mozilla.org/2004/em-rdf#">
-
-  <Description about="urn:mozilla:install-manifest">
-    <!-- Target Application this extension can install into,
-        with minimum and maximum supported versions. -->
-    <em:targetApplication>
-      <Description>
-        <!-- thunderbird -->
-        <em:id>{3550f703-e582-4d05-9a08-453d09bdfdc6}</em:id>
-        <em:minVersion>@THUNDERBIRD_VERSION@</em:minVersion>
-        <em:maxVersion>@THUNDERBIRD_MAXVERSION@</em:maxVersion>
-      </Description>
-    </em:targetApplication>
-
-    <em:targetApplication>
-      <Description>
-        <!-- seamonkey -->
-        <em:id>{92650c4d-4b8e-4d2a-b7eb-24ecf4f6b63a}</em:id>
-        <em:minVersion>@SEAMONKEY_VERSION@</em:minVersion>
-        <em:maxVersion>@SEAMONKEY_MAXVERSION@</em:maxVersion>
-      </Description>
-    </em:targetApplication>
-
-    <em:id>@XPI_EM_ID@</em:id>
-    <em:name>Lightning</em:name>
-    <em:version>@LIGHTNING_VERSION@</em:version> <!-- BuildID=@MOZ_BUILDID@ -->
-    <em:description>Integrated Calendaring &amp; Scheduling for your Email client</em:description>
-#ifdef LIGHTNING_PRERELEASE_VERSION
-    <em:developer>Build ID: @MOZ_BUILDID@</em:developer>
-#endif
-    <em:creator>Mozilla Calendar Project</em:creator>
-    <em:homepageURL>https://www.mozilla.org/projects/calendar/</em:homepageURL>
-    <em:iconURL>chrome://calendar/skin/cal-icon32.png</em:iconURL>
-    <em:optionsURL>chrome://messenger/content/preferences/preferences.xul</em:optionsURL>
-    <em:strictCompatibility>true</em:strictCompatibility>
-  </Description>
-</RDF>
+This file exists as a placeholder until https://bugzilla.mozilla.org/show_bug.cgi?id=1472123 is fixed.

new file mode 100644
--- /dev/null
+++ b/calendar/lightning/manifest.json
@@ -0,0 +1,23 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+#
+#filter substitution
+{
+  "manifest_version": 2,
+  "name": "Lightning",
+  "description": "Integrated Calendaring & Scheduling for your Email client",
+  "version": "@LIGHTNING_VERSION@",
+  "author": "Mozilla Calendar Project",
+  "homepage_url": "https://www.mozilla.org/projects/calendar/",
+  "legacy": true,
+  "applications": {
+    "gecko": {
+      "id": "@XPI_EM_ID@",
+      "strict_min_version": "@THUNDERBIRD_VERSION@"
+    }
+  },
+  "icons": {
+    "32": "chrome/skin/linux/calendar/cal-icon32.png"
+  }
+}

--- a/calendar/lightning/moz.build
+++ b/calendar/lightning/moz.build
@@ -19,17 +19,17 @@ TEST_DIRS += ['../test']
 if CONFIG['NIGHTLY_BUILD']:
     DIST_SUBDIR = 'extensions/{e2fda1a4-762b-4020-b5ad-a41df1933103}'
 else:
     DIST_SUBDIR = 'distribution/extensions/{e2fda1a4-762b-4020-b5ad-a41df1933103}'
 export('DIST_SUBDIR')
 
 FINAL_TARGET_PP_FILES += [
     'app.ini',
-    'install.rdf',
+    'manifest.json',
 ]
 
 JAR_MANIFESTS += ['jar.mn']
 
 USE_EXTENSION_MANIFEST = True
 export('USE_EXTENSION_MANIFEST')
 
 if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'windows':
@@ -38,16 +38,20 @@ elif CONFIG['MOZ_WIDGET_TOOLKIT'] == 'co
     DEFINES['THEME'] = 'osx'
 else:
     DEFINES['THEME'] = 'linux'
 
 JS_PREFERENCE_PP_FILES += [
     'content/lightning.js',
 ]
 
+FINAL_TARGET_FILES += [
+    'install.rdf',
+]
+
 FINAL_TARGET_FILES.timezones += [
     '../timezones/zones.json',
 ]
 
 with Files('**'):
     BUG_COMPONENT = ('Calendar', 'Lightning Only')
 
 with Files('content/suite-*'):