diff --git a/html/options.html b/html/options.html
index 4b692d5..c33ce36 100644
--- a/html/options.html
+++ b/html/options.html
@@ -75,11 +75,6 @@ <h2>Styling Options</h2>
                 <label for="headerColor">Header color:</label>
                 <input type="color" id="headerColor" value="#1a1a40">
             </div>
-            <div id="userColorContainer"></div>
-            <button id="addUserColor">Add User Color</button>
-            <div class="option-row">
-                <button id="resetTheme">Reset Theme to Default</button>
-            </div>
             <div class="option-row">
                 <label for="messageBubbleColor">Message Bubble Color:</label>
                 <input type="color" id="messageBubbleColor" value="#1e1e3f">
@@ -88,6 +83,11 @@ <h2>Styling Options</h2>
                 <label for="messageBubbleOpacity">Message Bubble Opacity:</label>
                 <input type="range" id="messageBubbleOpacity" min="0" max="100" value="70">
             </div>
+            <div id="userColorContainer"></div>
+            <button id="addUserColor">Add User Color</button>
+            <div class="option-row">
+                <button id="resetTheme">Reset Theme to Default</button>
+            </div>
         </section>
         
         <section>
@@ -122,7 +122,8 @@ <h2>Advanced Features</h2>
                 <input type="checkbox" id="showDestructTimer" checked>
             </div>
             <div class="option-row">
-                <button id="exportCodebook">Export Codebook with Settings</button>
+                <label for="caseInsensitiveEncryption">Case-insensitive Encryption (Codebook):</label>
+                <input type="checkbox" id="caseInsensitiveEncryption">
             </div>
         </section>
         
@@ -131,6 +132,9 @@ <h2>Data Management</h2>
             <div class="option-row">
                 <button id="clearDataBtn" class="danger-btn">Clear All Data and Reset Values</button>
             </div>
+            <div class="option-row">
+                <button id="exportCodebook">Export Codebook with Settings</button>
+            </div>
         </section>
         
         <div id="statusMsg"></div>
diff --git a/js/background.js b/js/background.js
index 9ceea1f..90b2e4b 100644
--- a/js/background.js
+++ b/js/background.js
@@ -115,10 +115,11 @@ function isValidMessage(request) {
 function processMessage(request, sendResponse) {
   let processedMessage = request.message;
   
-  chrome.storage.local.get(['codebook', 'mutedUsers', 'crypticPhrase'], function(result) {
+  chrome.storage.local.get(['codebook', 'mutedUsers', 'crypticPhrase', 'caseInsensitiveEncryption'], function(result) {
     const codebook = result.codebook || {};
     const mutedUsers = result.mutedUsers || [];
     const crypticPhrase = result.crypticPhrase || '\\d ! d';
+    const caseInsensitiveEncryption = result.caseInsensitiveEncryption || false;
     
     // Check if the message is from a muted user
     const username = extractUsername(processedMessage);
@@ -130,7 +131,17 @@ function processMessage(request, sendResponse) {
     if (request.action === "encrypt") {
       for (const key in codebook) {
         if (codebook.hasOwnProperty(key)) {
-          processedMessage = processedMessage.replace(new RegExp(escapeRegExp(key), 'g'), codebook[key]);
+          const regex = caseInsensitiveEncryption 
+            ? new RegExp(escapeRegExp(key), 'gi')
+            : new RegExp(escapeRegExp(key), 'g');
+          processedMessage = processedMessage.replace(regex, (match) => {
+            const replacement = codebook[key];
+            return caseInsensitiveEncryption ? replacement : (
+              match === match.toUpperCase() ? replacement.toUpperCase() :
+              match === match.toLowerCase() ? replacement.toLowerCase() :
+              replacement
+            );
+          });
         }
       }
       // Replace default cryptic phrase with custom one
@@ -141,7 +152,16 @@ function processMessage(request, sendResponse) {
       processedMessage = processedMessage.replace(new RegExp(escapeRegExp(crypticPhrase), 'g'), '\\d ! d');
       for (const key in codebook) {
         if (codebook.hasOwnProperty(key)) {
-          processedMessage = processedMessage.replace(new RegExp(escapeRegExp(codebook[key]), 'g'), key);
+          const regex = caseInsensitiveEncryption 
+            ? new RegExp(escapeRegExp(codebook[key]), 'gi')
+            : new RegExp(escapeRegExp(codebook[key]), 'g');
+          processedMessage = processedMessage.replace(regex, (match) => {
+            return caseInsensitiveEncryption ? key : (
+              match === match.toUpperCase() ? key.toUpperCase() :
+              match === match.toLowerCase() ? key.toLowerCase() :
+              key
+            );
+          });
         }
       }
       sendResponse({ decryptedMessage: processedMessage });
diff --git a/js/discord.js b/js/discord.js
index 30c3653..e792bbb 100644
--- a/js/discord.js
+++ b/js/discord.js
@@ -34,6 +34,12 @@ CrypticChat.Discord = {
             const contentElement = messageElement.querySelector('[id^="message-content-"]');
             if (!contentElement) return null;
 
+            // Ignore repliedTextPreview
+            const repliedTextPreview = messageElement.querySelector('[class*="repliedTextPreview_"]');
+            if (repliedTextPreview) {
+                return null;
+            }
+
             const originalText = contentElement.textContent.trim();
             let decryptedText = originalText;
             let isDecrypted = false;
diff --git a/js/options.js b/js/options.js
index 2f6115b..b32ccd5 100644
--- a/js/options.js
+++ b/js/options.js
@@ -69,6 +69,8 @@ document.addEventListener('DOMContentLoaded', function() {
     document.getElementById(id).addEventListener('change', debounce(autoSave, 500));
     document.getElementById(id).addEventListener('input', debounce(autoSave, 500));
   });
+
+  document.getElementById('caseInsensitiveEncryption').addEventListener('change', saveOptions);
 });
 
 function debounce(func, delay) {
@@ -129,7 +131,8 @@ function saveOptions(showMessage = true) {
         messageBubbleOpacity: document.getElementById('messageBubbleOpacity').value,
         userColors: getUserColors(),
         mutedUsers: getMutedUsers(),
-        autoSend: document.getElementById('autoSend').checked
+        autoSend: document.getElementById('autoSend').checked,
+        caseInsensitiveEncryption: document.getElementById('caseInsensitiveEncryption').checked
     };
 
     chrome.storage.local.set(options, function() {
@@ -160,7 +163,8 @@ function loadOptions() {
     'messageSpacing',
     'crypticPhrase',
     'messageBubbleColor',
-    'messageBubbleOpacity'
+    'messageBubbleOpacity',
+    'caseInsensitiveEncryption'
   ], function(items) {
     document.getElementById('codebookText').value = formatCodebook(items.codebook || {});
     document.getElementById('messagesToLoad').value = items.messagesToLoad || 50;
@@ -182,6 +186,7 @@ function loadOptions() {
     document.getElementById('crypticPhrase').value = items.crypticPhrase || '\\d ! d';
     document.getElementById('messageBubbleColor').value = items.messageBubbleColor || '#1e1e3f';
     document.getElementById('messageBubbleOpacity').value = items.messageBubbleOpacity || '70';
+    document.getElementById('caseInsensitiveEncryption').checked = items.caseInsensitiveEncryption || false;
   });
 }