diff --git a/frontend/src/app/shared/components/editor/components/ckeditor/ckeditor.types.ts b/frontend/src/app/shared/components/editor/components/ckeditor/ckeditor.types.ts
index 35dd84b2a9b..3b578071b5c 100644
--- a/frontend/src/app/shared/components/editor/components/ckeditor/ckeditor.types.ts
+++ b/frontend/src/app/shared/components/editor/components/ckeditor/ckeditor.types.ts
@@ -20,6 +20,10 @@ export interface CKEditorDomEventData {
   keyCode:number;
 }
 
+// Opaque handle for a parsed CKEditor model fragment (DocumentFragment).
+// We never inspect its internals, only pass it from data.parse to model.insertContent.
+export type CKEditorModelFragment = unknown;
+
 export interface ICKEditorInstance {
   id:string;
 
@@ -39,9 +43,13 @@ export interface ICKEditorInstance {
 
   listenTo(node:unknown, key:string, callback:(evt:CKEditorEvent, data:CKEditorDomEventData) => unknown, options:CKEditorListenOptions):void;
 
+  data:{
+    parse(data:string):CKEditorModelFragment;
+  };
   model:{
     on(ev:string, callback:() => unknown):void
     fire(ev:string, data:unknown):void
+    insertContent(content:CKEditorModelFragment):void
     document:{
       on(ev:string, callback:() => unknown):void
     };
diff --git a/frontend/src/stimulus/controllers/dynamic/work-packages/activities-tab/quote-comment.controller.ts b/frontend/src/stimulus/controllers/dynamic/work-packages/activities-tab/quote-comment.controller.ts
index 40d836b354c..25a26ff7916 100644
--- a/frontend/src/stimulus/controllers/dynamic/work-packages/activities-tab/quote-comment.controller.ts
+++ b/frontend/src/stimulus/controllers/dynamic/work-packages/activities-tab/quote-comment.controller.ts
@@ -65,19 +65,19 @@ export default class QuoteCommentController extends Controller {
       .join('');
 
     // if we ever change CKEditor or how @mentions work this will break
-    return `<mention class="mention" data-id="${userId}" data-type="user" data-text="@${userName}">@${userName}</mention> ${textWrote}:\n\n${quoted}`;
+    return `<mention class="mention" data-id="${userId}" data-type="user" data-text="@${userName}">@${userName}</mention> ${textWrote}:\n\n${quoted}\n\n`;
   }
 
   private insertQuoteOnExistingEditor(quotedText:string) {
-    if (this.ckEditorInstance) {
-      const editorData = this.ckEditorInstance.getData({ trim: false });
+    const editor = this.ckEditorInstance;
+    if (!editor) return;
 
-      if (editorData.endsWith('<br>') || editorData.endsWith('\n')) {
-        this.ckEditorInstance.setData(`${editorData}${quotedText}`);
-      } else {
-        this.ckEditorInstance.setData(`${editorData}\n\n${quotedText}`);
-      }
-    }
+    // insert at the current cursor position (preserved by CKEditor across blur/focus),
+    // then place focus so the user can type immediately after the blockquote
+    const fragment = editor.data.parse(quotedText);
+    editor.model.insertContent(fragment);
+
+    this.workPackagesActivitiesTabEditorOutlet.focusEditor();
   }
 
   private setCommentRestriction(isInternal:boolean) {
diff --git a/spec/features/activities/work_package/activities_spec.rb b/spec/features/activities/work_package/activities_spec.rb
index a51a855b57b..eaf918ae0fd 100644
--- a/spec/features/activities/work_package/activities_spec.rb
+++ b/spec/features/activities/work_package/activities_spec.rb
@@ -919,6 +919,9 @@ RSpec.describe "Work package activity", :js, :with_cuprite, with_ee: %i[internal
 
         # expect the quoted comment to be shown
         activity_tab.ckeditor.expect_include_value("@A Member wrote:\nFirst comment by member")
+
+        # expect the editor to be focused so the user can type immediately
+        activity_tab.expect_focus_on_editor
       end
     end
 
@@ -937,8 +940,11 @@ RSpec.describe "Work package activity", :js, :with_cuprite, with_ee: %i[internal
         # quote other user's comment
         activity_tab.quote_comment(first_comment_by_member)
 
-        # expect the original comment and quote are shown
+        # expect the original comment and quote are shown (quote appended after existing content)
         activity_tab.ckeditor.expect_include_value("Partial message:\n@A Member wrote:\nFirst comment by member")
+
+        # expect the editor to be focused so the user can type immediately
+        activity_tab.expect_focus_on_editor
       end
     end
   end