diff --git a/_locales/en/messages.json b/_locales/en/messages.json
index cdd3ad4d..4552126c 100644
--- a/_locales/en/messages.json
+++ b/_locales/en/messages.json
@@ -626,5 +626,13 @@
   "placeholder_author": {
     "message": "Author",
     "description": ""
+  },
+  "prefs_OptionText_placeholders_use_default_value": {
+    "message": "Placeholders: Use default value",
+    "description": ""
+  },
+  "prefs_OptionText_placeholders_use_default_value_info": {
+    "message": "If checked, the placeholders will be filled with the default values when no value is provided. Otherwise, the placeholders will be kept in place.",
+    "description": ""
   }
 }
\ No newline at end of file
diff --git a/js/mzta-menus.js b/js/mzta-menus.js
index 62c3502e..f1f54425 100644
--- a/js/mzta-menus.js
+++ b/js/mzta-menus.js
@@ -156,7 +156,8 @@ export class mzta_Menus {
                     }
                 }
                 // console.log(">>>>>>>>>> finalSubs: " + JSON.stringify(finalSubs));
-                fullPrompt = placeholdersUtils.replacePlaceholders(curr_prompt.text, finalSubs) + (String(curr_prompt.need_signature) == "1" ? " " + await this.getDefaultSignature():"") + " " + chatgpt_lang;
+                let prefs_ph = await browser.storage.sync.get({placeholders_use_default_value: false});
+                fullPrompt = placeholdersUtils.replacePlaceholders(curr_prompt.text, finalSubs, prefs_ph.placeholders_use_default_value) + (String(curr_prompt.need_signature) == "1" ? " " + await this.getDefaultSignature():"") + " " + chatgpt_lang;
             }
             
             switch(curr_prompt.id){
diff --git a/js/mzta-placeholders.js b/js/mzta-placeholders.js
index 60851f37..98ce7e30 100644
--- a/js/mzta-placeholders.js
+++ b/js/mzta-placeholders.js
@@ -36,63 +36,63 @@ const defaultPlaceholders = [
     {
         id: 'mail_body',
         name: "__MSG_placeholder_mail_body__",
-        text: "",
+        default_value: "",
         type: 0,
         is_default: "1",
     },
     {
         id: 'html_body',
         name: "__MSG_placeholder_html_body__",
-        text: "",
+        default_value: "",
         type: 0,
         is_default: "1",
     },
     {
         id: 'mail_subject',
         name: "__MSG_placeholder_mail_subject__",
-        text: "",
+        default_value: "",
         type: 0,
         is_default: "1",
     },
     {
         id: 'selected_text',
         name: "__MSG_placeholder_selected_text__",
-        text: "",
+        default_value: "",
         type: 0,
         is_default: "1",
     },
     {
         id: 'additional_text',  //TODO
         name: "__MSG_placeholder_additional_text__",
-        text: "",
+        default_value: "",
         type: 0,
         is_default: "1",
     },
     {
         id: 'junk_score',
         name: "__MSG_placeholder_junk_score__",
-        text: "",
+        default_value: "0",
         type: 1,
         is_default: "1",
     },
     {
         id: 'recipients',
         name: "__MSG_placeholder_recipients__",
-        text: "",
+        default_value: "",
         type: 0,
         is_default: "1",
     },
     {
         id: 'cc_list',
         name: "__MSG_placeholder_cc_list__",
-        text: "",
+        default_value: "",
         type: 0,
         is_default: "1",
     },
     {
         id: 'author',
         name: "__MSG_placeholder_author__",
-        text: "",
+        default_value: "",
         type: 0,
         is_default: "1",
     },
@@ -183,11 +183,12 @@ export const placeholdersUtils = {
         return matches;
     },
 
-    replacePlaceholders(text, replacements) {
+    replacePlaceholders(text, replacements, use_dafault_value = false) {
         // Regular expression to match patterns like {%...%}
         return text.replace(/{%\s*(.*?)\s*%}/g, function(match, p1) {
           // p1 contains the key inside {% %}
-          return replacements[p1] || match; // Replace if found, otherwise keep the original
+          // Replace if found, otherwise keep the original or substitute with default value
+          return replacements[p1] || use_dafault_value ? defaultPlaceholders.find(ph => ph.id === p1).default_value : match;
         });
     },
 
diff --git a/options/mzta-options-default.js b/options/mzta-options-default.js
index 1f055670..f3b41862 100644
--- a/options/mzta-options-default.js
+++ b/options/mzta-options-default.js
@@ -32,4 +32,5 @@ export const prefs_default = {
     openai_comp_chat_name: 'OpenAI Comp',
     dynamic_menu_force_enter: false,
     dynamic_menu_order_alphabet: true,
+    placeholders_use_default_value: false,
 }
\ No newline at end of file
diff --git a/options/mzta-options.html b/options/mzta-options.html
index 050d87b5..70ed66ac 100644
--- a/options/mzta-options.html
+++ b/options/mzta-options.html
@@ -81,6 +81,17 @@
           </label>
         </td>
       </tr>
+      <tr>
+        <td><label>
+          <span>__MSG_prefs_OptionText_placeholders_use_default_value__</span>
+        </label></td>
+        <td>
+          <label>
+            <input type="checkbox" id="placeholders_use_default_value" name="placeholders_use_default_value" class="option-input" />
+            &nbsp;<span>__MSG_prefs_OptionText_placeholders_use_default_value_info__</span>
+          </label>
+        </td>
+      </tr>
       <tr>
         <td>
           <label>