--- a/chat/content/conversation-browser.js
+++ b/chat/content/conversation-browser.js
@@ -426,17 +426,17 @@
      *
      * @param {imIMessage} msg - Message to use as replacement.
      */
     replaceMessage(msg) {
       if (!msg.remoteId) {
         // No remote id, nothing existing to replace.
         return;
       }
-      if (this._messageDisplayPending) {
+      if (this._messageDisplayPending || this._pendingMessages.length) {
         let pendingIndex = this._pendingMessages.findIndex(
           ({ msg: pendingMsg }) => pendingMsg.remoteId === msg.remoteId
         );
         if (
           pendingIndex > -1 &&
           pendingIndex >= this._nextPendingMessageIndex
         ) {
           this._pendingMessages[pendingIndex].msg = msg;