Update announcements banner after 2.27 release (#523)

* update announcements after 2.27 release

* update the table styling

Author: bilgeyucel

content/release-notes/2.27.0.md

@@ -1,13 +1,13 @@
----
-title: Haystack 2.27.0
-description: Release notes for Haystack 2.27.0
-toc: True
-date: 2026-04-01
-last_updated: 2026-04-01
-tags: ["Release Notes"]
-link: https://github.com/deepset-ai/haystack/releases/tag/v2.27.0
----
-
+---
+title: Haystack 2.27.0
+description: Release notes for Haystack 2.27.0
+toc: True
+date: 2026-04-01
+last_updated: 2026-04-01
+tags: ["Release Notes"]
+link: https://github.com/deepset-ai/haystack/releases/tag/v2.27.0
+---
+
 ## ⭐️ Highlights
 
 ### 🔌 Automatic List Joining in Pipeline
@@ -16,12 +16,15 @@ When a component expects a list as input, pipelines now automatically join multi
 
 Supported conversations:
 
+<div class="styled-table">
+
 Source Types | Target Type | Behavior
 -- | -- | --
 T + T | list[T] | Combines multiple inputs into a list of the same type.
 T + list[T] | list[T] | Merges single items and lists into a single list.
 str + ChatMessage | list[str] | Converts all inputs to `str` and combines into a list.
 str + ChatMessage | list[ChatMessage] | Converts all inputs to `ChatMessage` and combines into a list.
+</div>
 
 Learn more about how to simplify list joins in pipelines in [📖 Smart Pipeline Connections: Implicit List Joining](https://docs.haystack.deepset.ai/docs/smart-pipeline-connections#implicit-list-joining)
 
@@ -71,4 +74,4 @@ You can prototype locally in memory and easily debug, filter, and inspect the da
 
 ## 💙 Big thank you to everyone who contributed to this release!
 
-@aayushbaluni, @anakin87, @bilgeyucel, @bogdankostic, @Br1an67, @ComeOnOliver, @davidsbatista, @jnMetaCode, @julian-risch, @Krishnachaitanyakc, @maxdswain, @pandego, @RMartinWhozfoxy, @satishkc7, @sjrl, @srini047, @SyedShahmeerAli12, @v-tan, @xr843
+@aayushbaluni, @anakin87, @bilgeyucel, @bogdankostic, @Br1an67, @ComeOnOliver, @davidsbatista, @jnMetaCode, @julian-risch, @Krishnachaitanyakc, @maxdswain, @pandego, @RMartinWhozfoxy, @satishkc7, @sjrl, @srini047, @SyedShahmeerAli12, @v-tan, @xr843

themes/haystack/layouts/partials/announcement.html

@@ -22,13 +22,13 @@
     </div>
 </a> -->
 
-<a href="/release-notes/2.26.0" class="announcement-bar blue">
+<a href="/release-notes/2.27.0" class="announcement-bar blue">
   <div class="container">
      <!-- <span> 📚 Learn how to turn Haystack pipelines into production-ready <strong>REST APIs</strong> or <strong>MCP tools</strong></span> -->
       <!-- <span>🆕 <strong>Faster agents</strong> with parallel tool execution and <strong>guardrails & moderation</strong> for safer apps. See what's new in <strong>Haystack 2.15</strong> 🌟</span> -->
       <!-- <span>🆕 <strong>Haystack 2.18</strong>: Pipeline Error Recovery + Structured Output Generation</span> -->
       <!-- <span>📅 Join us in Berlin for <strong>AI Builders Unconference</strong> on Nov 25!</span> -->
-       <span> 🔎 <strong>Haystack 2.26 is here!</strong> <code>LLMRanker</code> for high-quality context & Jinja2 support for dynamic system prompts in Agents</span>
+       <span> 📣 <strong>Haystack 2.27 is here!</strong> Better DX for document stores & automatic list joining in pipelines</span>
       <span>
           <svg
       xmlns="http://www.w3.org/2000/svg"