• This is a simple Maven project placed in WSL file system with a default Hello World main method class. I use Java 21 on Windows, and Java 8 on WSL.

4.0.0

    <groupId>wsl.testing</groupId>
    <artifactId>WSLTesting</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <mavenpiler.source>8</mavenpiler.source>
        <mavenpiler.target>8</mavenpiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
   <build>
       <plugins>
           <plugin>
               <artifactId>maven-compiler-plugin</artifactId>
               <version>3.8.1</version>
               <configuration>
                   <source>1.8</source>
                   <target>1.8</target>
               </configuration>
           </plugin>
       </plugins>
   </build>

</project>

I have configured it to run on WSL in all possible places as shown in the screen shot and in other places. I set the JDK on the one I have in my Ubuntu machine. => It all boils down to Maven, then:
Regardless of the Maven home I use, if I DO NOT check "delegate IDE build/run to Maven"
I get the error:

Attempting to start build with JDK Java version "21.0.3+13", which is not stored in the project's WSL distribution. The JDK to run the build as well as JDK used by the project must be stored in the same WSL distribution where the project is stored. A JDK 11 or later is required to run the build. If your project uses older JDK, please add a JDK 11 or newer to your SDK configuration table. This JDK will be automatically picked up to run the build.

This happened when using Bundled Maven: And it also happens when using Maven installed on WSL:

When I delegate IDE build/run actions to Maven the result depends:

• Using bundled Maven:
• Using Ubuntu Maven:
• Checking or unchecking seems irrelevant:

Using WSL terminal and native Maven works But that means the IDE is not that useful. mvn clean compile exec:java -Dexec.mainClass="wsl.testing.Main"

=> I would like to know how to solve this and know why there is a difference when checking