Drop the use of range, as newer constructs make it mainly unnecessary.

compose.js

@@ -41,7 +41,6 @@ const {
   escapeHtml,
   getDefaultIdentity,
   getIdentities,
-  range,
   systemCharset,
 } = importRelative(this, "misc.js");
 const { msgHdrGetUri, getMail3Pane, msgHdrGetHeaders } = importRelative(
@@ -418,7 +417,7 @@ function replyAllParams(aIdentity, aMsgHdr, k) {
       if (emails.length) {
         // Invariant: at this stage, we only have one item in to.
         cc = cc.concat([to[0]]); // move the to in cc
-        to = [...range(0, names.length)].map(i => [names[i], emails[i]]);
+        to = names.map((n, i) => [n, emails[i]]);
       }
     }
     finish(to, cc, bcc);

misc.js

@@ -14,8 +14,6 @@ var EXPORTED_SYMBOLS = [
   "getIdentities",
   "getDefaultIdentity",
   "getIdentityForEmail",
-  // JS programming helpers
-  "range",
   // Various formatting helpers
   "dateAsInMessageList",
   "escapeHtml",
@@ -34,28 +32,6 @@ XPCOMUtils.defineLazyModuleGetters(this, {
   Services: "resource://gre/modules/Services.jsm",
 });
 
-if (!Services.intl) {
-  // That one doesn't belong to MailServices.
-  XPCOMUtils.defineLazyServiceGetter(
-    MailServices,
-    "i18nDateFormatter",
-    "@mozilla.org/intl/scriptabledateformat;1",
-    "nsIScriptableDateFormat"
-  );
-}
-
-/**
- * Python-style range function to use in list comprehensions.
- *  @param {Number} begin
- *  @param {Number} end
- *  @return {Generator} An iterator that yields from begin to end - 1.
- */
-function* range(begin, end) {
-  for (let i = begin; i < end; ++i) {
-    yield i;
-  }
-}
-
 /**
  * Returns the default identity in the form { boolean isDefault; nsIMsgIdentity identity }
  */
@@ -121,7 +97,7 @@ function getIdentityForEmail(anEmailAddress) {
 }
 
 /**
- * A stupid formatting function that uses the i18nDateFormatter XPCOM component
+ * A stupid formatting function that uses Services.intl
  * to format a date just like in the message list
  * @param {Date} aDate a javascript Date object
  * @return {String} a string containing the formatted date

send.js

@@ -30,7 +30,6 @@ function importRelative(that, path) {
   return ChromeUtils.import(new URL(path, that.__URI__));
 }
 
-const { range } = importRelative(this, "misc.js");
 const { msgUriToMsgHdr } = importRelative(this, "msgHdrUtils.js");
 const {
   determineComposeHtml,
@@ -244,9 +243,9 @@ function sendMessage(
         "Can't edit more than one message at a time"
       );
       let msgHdr = msgUriToMsgHdr(urls[0]);
-      references = [...range(0, msgHdr.numReferences)].map(i =>
-        msgHdr.getStringReference(i)
-      );
+      for (let i = 0; i < msgHdr.numReferences; i++) {
+        references.push(msgHdr.getStringReference(i));
+      }
       break;
     }
 
@@ -262,9 +261,9 @@ function sendMessage(
         "Can't reply to more than one message at a time"
       );
       let msgHdr = msgUriToMsgHdr(urls[0]);
-      references = [...range(0, msgHdr.numReferences)].map(i =>
-        msgHdr.getStringReference(i)
-      );
+      for (let i = 0; i < msgHdr.numReferences; i++) {
+        references.push(msgHdr.getStringReference(i));
+      }
       references.push(msgHdr.messageId);
       break;
     }