diff --git a/src/xhrInterceptor/responseModifiers/flattenThread.js b/src/xhrInterceptor/responseModifiers/flattenThread.js
index 6828772..23db6eb 100644
--- a/src/xhrInterceptor/responseModifiers/flattenThread.js
+++ b/src/xhrInterceptor/responseModifiers/flattenThread.js
@@ -71,13 +71,13 @@
     }
 
     let prevId;
-    if (parentId === prevReplyParentId && prevReplyParentId)
+    if (parentId == prevReplyParentId && prevReplyParentId)
       prevId = prevReplyId;
     else
       prevId = parentId;
 
     const prevMessage =
-        prevId ? mogs.find(m => m.getId() === prevId) : null;
+        prevId ? mogs.find(m => m.getId() == prevId) : null;
 
     return {
       isComment: true,
@@ -86,8 +86,8 @@
       parentId,
       prevMessage: {
         id: prevId,
-        payload: prevMessage.getPayload(),
-        author: prevMessage.getAuthor(),
+        payload: prevMessage?.getPayload(),
+        author: prevMessage?.getAuthor(),
       },
     };
   }
diff --git a/src/xhrInterceptor/responseModifiers/index.js b/src/xhrInterceptor/responseModifiers/index.js
index 2d0b7ce..43ffe6c 100644
--- a/src/xhrInterceptor/responseModifiers/index.js
+++ b/src/xhrInterceptor/responseModifiers/index.js
@@ -54,11 +54,11 @@
     });
   }
 
-  async intercept(request, response) {
+  async intercept(request) {
     const matchingModifiers = await this.#getMatchingModifiers(request);
 
     // If we didn't find any matching modifiers, return the response right away.
-    if (matchingModifiers.length === 0) return response;
+    if (matchingModifiers.length === 0) return request.xhr.response;
 
     // Otherwise, apply the modifiers sequentially and set the new response.
     let json = getResponseJSON({
@@ -70,7 +70,7 @@
     for (const modifier of matchingModifiers) {
       json = await modifier.interceptor(request, json);
     }
-    response = convertJSONToResponse(request, json);
+    const response = convertJSONToResponse(request, json);
     request.$newResponse = response;
     request.$responseModified = true;
   }
diff --git a/src/xhrInterceptor/responseModifiers/loadMoreThread.js b/src/xhrInterceptor/responseModifiers/loadMoreThread.js
index f8da127..abea505 100644
--- a/src/xhrInterceptor/responseModifiers/loadMoreThread.js
+++ b/src/xhrInterceptor/responseModifiers/loadMoreThread.js
@@ -38,8 +38,9 @@
     }
 
     const messageOrGapPromises = [];
-    messageOrGapPromises.push(Promise.resolve(mogs));
-    for (const mog of mogs) {
+    messageOrGapPromises.push(
+        Promise.resolve(mogs.filter(mog => mog !== undefined)));
+    mogs.forEach(mog => {
       if (mog instanceof GapModel) {
         messageOrGapPromises.push(this.loadGap(forumId, threadId, mog));
       }
@@ -50,7 +51,7 @@
           }
         });
       }
-    }
+    });
 
     return Promise.all(messageOrGapPromises).then(res => {
       // #!if !production
@@ -60,6 +61,7 @@
       // #!if !production
       console.timeEnd('mergeMessages');
       // #!endif
+
       if (mogs.some(mog => {
             return mog instanceof GapModel ||
                 mog.getCommentsAndGaps().some(cog => cog instanceof GapModel);