diff --git a/app/javascript/dashboard/components-next/NewConversation/components/ComposeNewConversationForm.vue b/app/javascript/dashboard/components-next/NewConversation/components/ComposeNewConversationForm.vue
index 77267707b..74836219b 100644
--- a/app/javascript/dashboard/components-next/NewConversation/components/ComposeNewConversationForm.vue
+++ b/app/javascript/dashboard/components-next/NewConversation/components/ComposeNewConversationForm.vue
@@ -200,6 +200,7 @@ const setSelectedContact = async ({ value, action, ...rest }) => {
 
 const handleInboxAction = ({ value, action, ...rest }) => {
   v$.value.$reset();
+  state.message = '';
   emit('updateTargetInbox', { ...rest });
   showInboxesDropdown.value = false;
   state.attachedFiles = [];
@@ -220,6 +221,7 @@ const removeSignatureFromMessage = () => {
 const removeTargetInbox = value => {
   v$.value.$reset();
   removeSignatureFromMessage();
+  state.message = '';
   emit('updateTargetInbox', value);
   state.attachedFiles = [];
 };
@@ -227,6 +229,7 @@ const removeTargetInbox = value => {
 const clearSelectedContact = () => {
   removeSignatureFromMessage();
   emit('clearSelectedContact');
+  state.message = '';
   state.attachedFiles = [];
 };
 
diff --git a/app/javascript/dashboard/components-next/NewConversation/components/MessageEditor.vue b/app/javascript/dashboard/components-next/NewConversation/components/MessageEditor.vue
index 2cda75e53..ef523a288 100644
--- a/app/javascript/dashboard/components-next/NewConversation/components/MessageEditor.vue
+++ b/app/javascript/dashboard/components-next/NewConversation/components/MessageEditor.vue
@@ -1,9 +1,10 @@
 <script setup>
+import { computed } from 'vue';
 import { useI18n } from 'vue-i18n';
 
 import Editor from 'dashboard/components-next/Editor/Editor.vue';
 
-defineProps({
+const props = defineProps({
   hasErrors: { type: Boolean, default: false },
   hasAttachments: { type: Boolean, default: false },
   sendWithSignature: { type: Boolean, default: false },
@@ -12,6 +13,8 @@ defineProps({
   medium: { type: String, default: '' },
 });
 
+const editorKey = computed(() => `editor-${props.channelType}-${props.medium}`);
+
 const { t } = useI18n();
 
 const modelValue = defineModel({
@@ -23,6 +26,7 @@ const modelValue = defineModel({
 <template>
   <div class="flex-1 h-full" :class="[!hasAttachments && 'min-h-[200px]']">
     <Editor
+      :key="editorKey"
       v-model="modelValue"
       :placeholder="
         t('COMPOSE_NEW_CONVERSATION.FORM.MESSAGE_EDITOR.PLACEHOLDER')
diff --git a/app/javascript/dashboard/components/widgets/conversation/ReplyBox.vue b/app/javascript/dashboard/components/widgets/conversation/ReplyBox.vue
index 6f955ffd5..d4c473801 100644
--- a/app/javascript/dashboard/components/widgets/conversation/ReplyBox.vue
+++ b/app/javascript/dashboard/components/widgets/conversation/ReplyBox.vue
@@ -7,7 +7,9 @@ import { useTrack } from 'dashboard/composables';
 import keyboardEventListenerMixins from 'shared/mixins/keyboardEventListenerMixins';
 import { FEATURE_FLAGS } from 'dashboard/featureFlags';
 
+import CannedResponse from './CannedResponse.vue';
 import ReplyToMessage from './ReplyToMessage.vue';
+import ResizableTextArea from 'shared/components/ResizableTextArea.vue';
 import AttachmentPreview from 'dashboard/components/widgets/AttachmentsPreview.vue';
 import ReplyTopPanel from 'dashboard/components/widgets/WootWriter/ReplyTopPanel.vue';
 import ReplyEmailHead from './ReplyEmailHead.vue';
@@ -44,6 +46,7 @@ import {
   appendSignature,
   removeSignature,
   getEffectiveChannelType,
+  extractTextFromMarkdown,
 } from 'dashboard/helper/editorHelper';
 
 import { LOCAL_STORAGE_KEYS } from 'dashboard/constants/localStorage';
@@ -69,6 +72,8 @@ export default {
     WhatsappTemplates,
     WootMessageEditor,
     QuotedEmailPreview,
+    ResizableTextArea,
+    CannedResponse,
   },
   mixins: [inboxMixin, fileUploadMixin, keyboardEventListenerMixins],
   props: {
@@ -109,6 +114,8 @@ export default {
       recordingAudioState: '',
       recordingAudioDurationText: '',
       replyType: REPLY_EDITOR_MODES.REPLY,
+      mentionSearchKey: '',
+      hasSlashCommand: false,
       bccEmails: '',
       ccEmails: '',
       toEmails: '',
@@ -137,9 +144,12 @@ export default {
       isFeatureEnabledonAccount: 'accounts/isFeatureEnabledonAccount',
     }),
     currentContact() {
-      return this.$store.getters['contacts/getContact'](
-        this.currentChat.meta.sender.id
-      );
+      const senderId = this.currentChat?.meta?.sender?.id;
+      if (!senderId) return {};
+      return this.$store.getters['contacts/getContact'](senderId);
+    },
+    isRichEditorEnabled() {
+      return this.isAWebWidgetInbox || this.isAnEmailChannel || this.isAPIInbox;
     },
     shouldShowReplyToMessage() {
       return (
@@ -396,6 +406,26 @@ export default {
         !!this.quotedEmailText
       );
     },
+    showRichContentEditor() {
+      if (this.isOnPrivateNote || this.isRichEditorEnabled) {
+        return true;
+      }
+
+      if (this.isAPIInbox) {
+        const {
+          display_rich_content_editor: displayRichContentEditor = false,
+        } = this.uiSettings;
+        return displayRichContentEditor;
+      }
+
+      return false;
+    },
+    // ensure that the signature is plain text depending on `showRichContentEditor`
+    signatureToApply() {
+      return this.showRichContentEditor
+        ? this.messageSignature
+        : extractTextFromMarkdown(this.messageSignature);
+    },
   },
   watch: {
     currentChat(conversation, oldConversation) {
@@ -438,7 +468,25 @@ export default {
         this.resetRecorderAndClearAttachments();
       }
     },
-    message() {
+    message(updatedMessage) {
+      // Check if the message starts with a slash.
+      const bodyWithoutSignature = removeSignature(
+        updatedMessage,
+        this.signatureToApply
+      );
+      const startsWithSlash = bodyWithoutSignature.startsWith('/');
+
+      // Determine if the user is potentially typing a slash command.
+      // This is true if the message starts with a slash and the rich content editor is not active.
+      this.hasSlashCommand = startsWithSlash && !this.showRichContentEditor;
+      this.showMentions = this.hasSlashCommand;
+
+      // If a slash command is active, extract the command text after the slash.
+      // If not, reset the mentionSearchKey.
+      this.mentionSearchKey = this.hasSlashCommand
+        ? bodyWithoutSignature.substring(1)
+        : '';
+
       // Autosave the current message draft.
       this.doAutoSaveDraft();
     },
@@ -488,14 +536,20 @@ export default {
   methods: {
     handleInsert(article) {
       const { url, title } = article;
-      // Removing empty lines from the title
-      const lines = title.split('\n');
-      const nonEmptyLines = lines.filter(line => line.trim() !== '');
-      const filteredMarkdown = nonEmptyLines.join(' ');
-      emitter.emit(
-        BUS_EVENTS.INSERT_INTO_RICH_EDITOR,
-        `[${filteredMarkdown}](${url})`
-      );
+      if (this.isRichEditorEnabled) {
+        // Removing empty lines from the title
+        const lines = title.split('\n');
+        const nonEmptyLines = lines.filter(line => line.trim() !== '');
+        const filteredMarkdown = nonEmptyLines.join(' ');
+        emitter.emit(
+          BUS_EVENTS.INSERT_INTO_RICH_EDITOR,
+          `[${filteredMarkdown}](${url})`
+        );
+      } else {
+        this.addIntoEditor(
+          `${this.$t('CONVERSATION.REPLYBOX.INSERT_READ_MORE')} ${url}`
+        );
+      }
 
       useTrack(CONVERSATION_EVENTS.INSERT_ARTICLE_LINK);
     },
@@ -564,14 +618,26 @@ export default {
       if (this.isPrivate) {
         return message;
       }
-
-      const effectiveChannelType = getEffectiveChannelType(
-        this.channelType,
-        this.inbox?.medium || ''
-      );
+      if (this.showRichContentEditor) {
+        const effectiveChannelType = getEffectiveChannelType(
+          this.channelType,
+          this.inbox?.medium || ''
+        );
+        return this.sendWithSignature
+          ? appendSignature(
+              message,
+              this.messageSignature,
+              effectiveChannelType
+            )
+          : removeSignature(
+              message,
+              this.messageSignature,
+              effectiveChannelType
+            );
+      }
       return this.sendWithSignature
-        ? appendSignature(message, this.messageSignature, effectiveChannelType)
-        : removeSignature(message, this.messageSignature, effectiveChannelType);
+        ? appendSignature(message, this.signatureToApply)
+        : removeSignature(message, this.signatureToApply);
     },
     removeFromDraft() {
       if (this.conversationIdByRoute) {
@@ -587,6 +653,7 @@ export default {
         Escape: {
           action: () => {
             this.hideEmojiPicker();
+            this.hideMentions();
           },
           allowOnFocusedInput: true,
         },
@@ -629,6 +696,9 @@ export default {
     },
     onPaste(e) {
       const data = e.clipboardData.files;
+      if (!this.showRichContentEditor && data.length !== 0) {
+        this.$refs.messageInput.$el.blur();
+      }
       if (!data.length || !data[0]) {
         return;
       }
@@ -762,15 +832,19 @@ export default {
         // if signature is enabled, append it to the message
         // appendSignature ensures that the signature is not duplicated
         // so we don't need to check if the signature is already present
-        const effectiveChannelType = getEffectiveChannelType(
-          this.channelType,
-          this.inbox?.medium || ''
-        );
-        message = appendSignature(
-          message,
-          this.messageSignature,
-          effectiveChannelType
-        );
+        if (this.showRichContentEditor) {
+          const effectiveChannelType = getEffectiveChannelType(
+            this.channelType,
+            this.inbox?.medium || ''
+          );
+          message = appendSignature(
+            message,
+            this.messageSignature,
+            effectiveChannelType
+          );
+        } else {
+          message = appendSignature(message, this.signatureToApply);
+        }
       }
 
       const updatedMessage = replaceVariablesInMessage({
@@ -794,30 +868,52 @@ export default {
       });
       if (canReply || this.isAWhatsAppChannel || this.isAPIInbox)
         this.replyType = mode;
-      if (this.isRecordingAudio) {
-        this.toggleAudioRecorder();
+      if (this.showRichContentEditor) {
+        if (this.isRecordingAudio) {
+          this.toggleAudioRecorder();
+        }
+        return;
       }
+      this.$nextTick(() => this.$refs.messageInput.focus());
     },
     clearEditorSelection() {
       this.updateEditorSelectionWith = '';
     },
+    insertIntoTextEditor(text, selectionStart, selectionEnd) {
+      const { message } = this;
+      const newMessage =
+        message.slice(0, selectionStart) +
+        text +
+        message.slice(selectionEnd, message.length);
+      this.message = newMessage;
+    },
     addIntoEditor(content) {
-      this.updateEditorSelectionWith = content;
-      this.onFocus();
+      if (this.showRichContentEditor) {
+        this.updateEditorSelectionWith = content;
+        this.onFocus();
+      }
+      if (!this.showRichContentEditor) {
+        const { selectionStart, selectionEnd } = this.$refs.messageInput.$el;
+        this.insertIntoTextEditor(content, selectionStart, selectionEnd);
+      }
     },
     clearMessage() {
       this.message = '';
       if (this.sendWithSignature && !this.isPrivate) {
         // if signature is enabled, append it to the message
-        const effectiveChannelType = getEffectiveChannelType(
-          this.channelType,
-          this.inbox?.medium || ''
-        );
-        this.message = appendSignature(
-          this.message,
-          this.messageSignature,
-          effectiveChannelType
-        );
+        if (this.showRichContentEditor) {
+          const effectiveChannelType = getEffectiveChannelType(
+            this.channelType,
+            this.inbox?.medium || ''
+          );
+          this.message = appendSignature(
+            this.message,
+            this.messageSignature,
+            effectiveChannelType
+          );
+        } else {
+          this.message = appendSignature(this.message, this.signatureToApply);
+        }
       }
       this.attachedFiles = [];
       this.isRecordingAudio = false;
@@ -852,6 +948,9 @@ export default {
         this.toggleEmojiPicker();
       }
     },
+    hideMentions() {
+      this.showMentions = false;
+    },
     onTypingOn() {
       this.toggleTyping('on');
     },
@@ -1098,6 +1197,13 @@ export default {
         :message="inReplyTo"
         @dismiss="resetReplyToMessage"
       />
+      <CannedResponse
+        v-if="showMentions && hasSlashCommand"
+        v-on-clickaway="hideMentions"
+        class="normal-editor__canned-box"
+        :search-key="mentionSearchKey"
+        @replace="replaceText"
+      />
       <EmojiInput
         v-if="showEmojiPicker"
         v-on-clickaway="hideEmojiPicker"
@@ -1121,7 +1227,23 @@ export default {
         @play="recordingAudioState = 'playing'"
         @pause="recordingAudioState = 'paused'"
       />
+      <ResizableTextArea
+        v-else-if="!showRichContentEditor"
+        ref="messageInput"
+        v-model="message"
+        class="rounded-none input"
+        :placeholder="messagePlaceHolder"
+        :min-height="4"
+        :signature="signatureToApply"
+        allow-signature
+        :send-with-signature="sendWithSignature"
+        @typing-off="onTypingOff"
+        @typing-on="onTypingOn"
+        @focus="onFocus"
+        @blur="onBlur"
+      />
       <WootMessageEditor
+        v-else
         v-model="message"
         :editor-id="editorStateId"
         class="input popover-prosemirror-menu"
@@ -1247,6 +1369,10 @@ export default {
 
 .reply-box__top {
   @apply relative py-0 px-4 -mt-px;
+
+  textarea {
+    @apply shadow-none outline-none border-transparent bg-transparent m-0 max-h-60 min-h-[3rem] pt-4 pb-0 px-0 resize-none;
+  }
 }
 
 .emoji-dialog {
@@ -1266,4 +1392,9 @@ export default {
     @apply ltr:left-1 rtl:right-1 -bottom-2;
   }
 }
+
+.normal-editor__canned-box {
+  width: calc(100% - 2 * 1rem);
+  left: 1rem;
+}
 </style>
diff --git a/app/javascript/shared/components/ResizableTextArea.vue b/app/javascript/shared/components/ResizableTextArea.vue
index 4dda62cf9..78318fb49 100644
--- a/app/javascript/shared/components/ResizableTextArea.vue
+++ b/app/javascript/shared/components/ResizableTextArea.vue
@@ -111,10 +111,15 @@ export default {
     // watcher, this means that if the value is true, the signature
     // is supposed to be added, else we remove it.
     toggleSignatureInEditor(signatureEnabled) {
-      const valueWithSignature = signatureEnabled
+      let valueWithSignature = signatureEnabled
         ? appendSignature(this.modelValue, this.cleanedSignature)
         : removeSignature(this.modelValue, this.cleanedSignature);
 
+      // Clean up whitespace when removing signature from empty body
+      if (!signatureEnabled && !valueWithSignature.trim()) {
+        valueWithSignature = '';
+      }
+
       this.$emit('update:modelValue', valueWithSignature);
       this.$emit('input', valueWithSignature);