java 21 gives wrong error: Syntax error on token "RestrictedIdentifierWhen"

[mwensveen-ebpi]

When using org.mockito.Mockito.when as static import and on the first line of a method Eclipse will show an error:
Syntax error on token "RestrictedIdentifierWhen"

for example (part of the code):

import static org.mockito.Mockito.when;

    public String methodWithBug() {
        when(bug.methodWithBug()).thenReturn("bug");
        return "";
    }

When the when is not the first line of the method no error .
When using the fqn of the when method is used also no error.

When changing to java version 20 there are no compile errors.
bug.zip

See the small attached maven project.

Environment:
new install of eclipse-java-2023-09-R-linux-gtk-x86_64 with the Java 21 Support for Eclipse 2023-09 (4.29) plugin installed from the market place

[iloveeclipse]

Please check latest 4.30 nightly, it should be fixed.

Closing as duplicate of #456

[mwensveen-ebpi]

I can confirm that it is fixed in the 4.30 nightly