Ubuntu – Cannot have more than one RequestParam in my RestController

I get a very basic error when trying to create a very basic Spring RestController. I must be missing something very basic here.

To reproduce:

• Create a new Spring project with Spring Web here: https://start.spring.io/
• Add the following Controller:

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class WeirdErrorController {
    @GetMapping("/test")
    public String tryIt(
        @RequestParam(value = "a") String a,
        @RequestParam(value = "b") String b
    ) {
        return ("Here are the args: " + a + ", " + b);
    }
}

• Run it with ./gradlew bootRun.

• Make a request:

curl http://localhost:8080/test?a=foo&b=bar

Get this error:

Required request parameter 'b' for method parameter type String is not present]

I am running this on Ubuntu 22.04 in WSL2 in Win 11.
I have tested this in multiple configurations with the same result. Tried both Java 17 and Java 21. Is this a WSL2 related bug?