Error on unnamed variable (JDK 21 Preview)

Unnamed variables have been added to JDK 21 as a preview feature (https://openjdk.org/jeps/443). When formatting the source code with an unnamed variable, google-java-format throws an exception.

Caused by: com.google.googlejavaformat.java.FormatterException: 102:8: error: expected token: '_'; generated  instead
        at com.google.googlejavaformat.java.Formatter.getFormatReplacements(Formatter.java:275)
        at com.google.googlejavaformat.java.Formatter.formatSource(Formatter.java:247)
        at com.google.googlejavaformat.java.Formatter.formatSource(Formatter.java:213)
        at java.base@21.0.1/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
        ... 169 more