Apply patch from https://github.com/Martii

adam-p#577 (comment)

src/manifest.json

@@ -12,7 +12,7 @@
     "128": "common/images/icon128.png",
     "512": "common/images/icon512.png"
   },
-  "permissions": ["contextMenus", "storage"],
+  "permissions": ["menus", "storage"],
   "background": {"page": "chrome/background.html"},
   "content_scripts": [
     {
@@ -46,7 +46,15 @@
 
   ,"applications": {
     "gecko": {
-      "id": "[email protected]"
+      "id": "[email protected]",
+      "strict_min_version": "68.0"
+    }
+  }
+  ,"legacy": {
+    "type": "xul",
+    "options": {
+      "page": "common/options.html",
+      "open_in_tab": true
     }
   }
 }

utils/build.js

@@ -9,7 +9,7 @@
 var fs = require('fs');
 var file = require('file');
 var archiver = require('archiver');
-var MetaScript = require('MetaScript');
+var MetaScript = require('metascript');
 
 
 var BASE_DIR = '..';
@@ -22,7 +22,7 @@ var THUNDERBIRD_EXTENSION = file.path.join(DIST_DIR, 'thunderbird.xpi');
 
 var CHROME_INPUT = [/^manifest\.json$/, /^common(\\|\/)/, /^chrome(\\|\/)/, /^_locales(\\|\/)/];
 var FIREFOX_INPUT = CHROME_INPUT;
-var THUNDERBIRD_INPUT = [/^chrome.manifest$/, /^install.rdf$/, /^common(\\|\/)/, /^firefox(\\|\/)/];
+var THUNDERBIRD_INPUT = [/^manifest\.json$/, /^chrome.manifest$/, /^install.rdf$/, /^common(\\|\/)/, /^firefox(\\|\/)/, /^_locales(\\|\/)/];
 
 var CHROME_PLATFORM = 'chrome';
 var FIREFOX_PLATFORM = 'firefox';