diff --git a/public/script.js b/public/script.js
index 6e11186f5..9123ad32b 100644
--- a/public/script.js
+++ b/public/script.js
@@ -5930,6 +5930,7 @@ export async function saveReply(type, getMessage, fromStreaming, title, swipes,
             chat[chat.length - 1]['extra']['api'] = getGeneratingApi();
             chat[chat.length - 1]['extra']['model'] = getGeneratingModel();
             chat[chat.length - 1]['extra']['reasoning'] = reasoning;
+            chat[chat.length - 1]['extra']['reasoning_duration'] = null;
             if (power_user.message_token_count_enabled) {
                 const tokenCountText = (reasoning || '') + chat[chat.length - 1]['mes'];
                 chat[chat.length - 1]['extra']['token_count'] = await getTokenCountAsync(tokenCountText, 0);
@@ -5952,6 +5953,7 @@ export async function saveReply(type, getMessage, fromStreaming, title, swipes,
         chat[chat.length - 1]['extra']['api'] = getGeneratingApi();
         chat[chat.length - 1]['extra']['model'] = getGeneratingModel();
         chat[chat.length - 1]['extra']['reasoning'] = reasoning;
+        chat[chat.length - 1]['extra']['reasoning_duration'] = null;
         if (power_user.message_token_count_enabled) {
             const tokenCountText = (reasoning || '') + chat[chat.length - 1]['mes'];
             chat[chat.length - 1]['extra']['token_count'] = await getTokenCountAsync(tokenCountText, 0);
@@ -5971,6 +5973,7 @@ export async function saveReply(type, getMessage, fromStreaming, title, swipes,
         chat[chat.length - 1]['extra']['api'] = getGeneratingApi();
         chat[chat.length - 1]['extra']['model'] = getGeneratingModel();
         chat[chat.length - 1]['extra']['reasoning'] += reasoning;
+        // We don't know if the reasoning duration extended, so we don't update it here on purpose.
         if (power_user.message_token_count_enabled) {
             const tokenCountText = (reasoning || '') + chat[chat.length - 1]['mes'];
             chat[chat.length - 1]['extra']['token_count'] = await getTokenCountAsync(tokenCountText, 0);
@@ -5990,6 +5993,7 @@ export async function saveReply(type, getMessage, fromStreaming, title, swipes,
         chat[chat.length - 1]['extra']['api'] = getGeneratingApi();
         chat[chat.length - 1]['extra']['model'] = getGeneratingModel();
         chat[chat.length - 1]['extra']['reasoning'] = reasoning;
+        chat[chat.length - 1]['extra']['reasoning_duration'] = null;
         if (power_user.trim_spaces) {
             getMessage = getMessage.trim();
         }