Changing Accept Header in PreMatching filter doesn't affect routing

[myroch]

Describe the bug

After the switch to resteasy reactive my request filters don't work anymore.

Expected behavior

Accept Header set in the pre-matching request filter shall decide the routing to the resource.

Actual behavior

Setting the Accept Header inside the pre-matching request filter doesn't affect routing.

How to Reproduce?

Having following filter:

@PreMatching
@Provider
public class SetAcceptHeaderFilter implements ContainerRequestFilter {

    @Override
    public void filter(ContainerRequestContext requestContext) {
        requestContext.getHeaders().putSingle(HttpHeaders.ACCEPT, MediaType.TEXT_PLAIN);
    }
}

and following Resource:

@Path("/hello")
public class GreetingResource {
    @GET
    @Produces(MediaType.TEXT_PLAIN)
    public Response helloText() { return Response.ok("correct").build(); }

    @GET
    @Produces(MediaType.TEXT_HTML)
    public Response helloHtml() { return Response.ok("shall not happen").build(); }

Try to call it from the browser.

Output of uname -a or ver

No response

Output of java -version

java 17.0.9 2023-10-17 LTS

Quarkus version or git rev

2.6.12.Final and 3.6.4

Build tool (ie. output of mvnw --version or gradlew --version)

Apache Maven 3.6.3

Additional information

Do you know some workaround to this issue? Such a thing shall be pretty common. I'm trying to implement CXF's _type Query Parameter,

[geoand]

Thanks for reporting. #38131 fixes the issue

[quarkus-bot]

/cc @FroMage (resteasy-reactive), @stuartwdouglas (resteasy-reactive)