Release timeline: Release Schedule, Apache NetBeans 12.4 is scheduled to be released May 15th - 30th, 2021.

Pull requests integrated in 12.4:

https://github.com/apache/netbeans/milestone/12?closed=1

Java Enhancements

• Java 16 Support
  Java 16, the latest release of Java at the time of Apache NetBeans 12.4, is supported, including nb-javac which has been upgraded to support Java 16. 

  • nbjavac-upgrade-to-jdk-16: https://github.com/apache/netbeans/pull/2899
  • Replace usage of JDK internal, or in-house Base64 codecs by java.util.Base64: https://github.com/apache/netbeans/pull/2874
    
    

• Install OpenJDK 
  Go to Tools | Java Platform, click Add Platform, and then "Remote Universal OpenJDK Service", and you'll be able to download and register OpenJDK distros of your choice.
  https://github.com/apache/netbeans/pull/2854
  https://github.com/apache/netbeans/pull/2896
  
  

• Jakarta EE
  • Jakarta EE 9 Project Support: https://github.com/apache/netbeans/pull/2684
    
    
• Micronaut
  In the New Project dialog, choose "Java with Maven" and then "Micronaut Project", to get started with Micronaut development in Apache NetBeans 12.4.
  
  • New Micronaut project wizard
  • Code completion in Micronaut yaml config files implemented
  • HyperlinkProvider for Micronaut yaml config files implemented
  • WhereUsed RefactoringPlugin for Micronaut yaml config files implemented

          https://github.com/apache/netbeans/pull/2812

• Payara
  Automatically detect & list Payara Platform version in the server registration panel: https://github.com/apache/netbeans/pull/2409
  
  
• Maven
  
  • Support for VM/app argument injection to (Maven) run and debug project actions: https://github.com/apache/netbeans/pull/2731
  • Avoid NPE when executing some Maven projects: https://github.com/apache/netbeans/pull/2833
    
    
• Gradle
  • Upgrade Gradle Tooling to 7.0: https://github.com/apache/netbeans/pull/2861
  • Support Gradle Source Groups from Alien Projects: https://github.com/apache/netbeans/pull/2779
  • Fix NPE on Gradle settings when no network connection: https://github.com/apache/netbeans/pull/2879
  • Upgradle to JaCoCo 0.8.6 for Gradle Code Coverage: https://github.com/apache/netbeans/pull/2893
  • Clear NB Non-Project cache when we have more info from Gradle: https://github.com/apache/netbeans/pull/2837
    
    
• Ant
  • Support Ant Freeform projects with source Level 9+: https://github.com/apache/netbeans/pull/2794
  • Update nbbuild freeform project to open without errors: https://github.com/apache/netbeans/pull/2798
  • Improve Java/Jakarta EE with Ant based projects: https://github.com/apache/netbeans/pull/2491

PHP Enhancements

• PHP 8.0 Support: Named Arguments: https://github.com/apache/netbeans/pull/2894
• Prevent generating abstract methods with PHPDoc return array type: https://github.com/apache/netbeans/pull/2886
• Improved Fix Uses dialog: https://github.com/apache/netbeans/pull/2755
• Fixed compatibility with Phing 3: https://github.com/apache/netbeans/pull/2776
• Show new configuration files for PHP-CS-Fixer 3 in Important files : https://github.com/apache/netbeans/pull/2880

HTML

• Improved code completion for HTML forms: https://github.com/apache/netbeans/pull/2739

Miscellaneous Enhancements

• Markdown
  Files with extension ".md" are recognized, with a special icon, and basic syntax coloring: https://github.com/apache/netbeans/pull/1428
  
  
• FlatLaf Enhancements
  • Update FlatLaf from 1.0 to 1.1.1 and added "FlatLaf" options: https://github.com/apache/netbeans/pull/2839
  • Fix/improve styling of quicksearch field in menubar: https://github.com/apache/netbeans/pull/2900
  • Update from 1.1.1 to 1.1.2 and fix/improve options: https://github.com/apache/netbeans/pull/2872
    
    
• Always display errors as an icon in bottom right corner in development builds: https://github.com/apache/netbeans/pull/2888

Reference: Complete Listing of Closed PRs for 12.4