How to make viewController ignore server.servlet.context-path

Question

I have the following configuration for serving static content from Spring Boot.

    @Configuration
    public class WebConfig implements WebMvcConfigurer {

        @Value("${frontend.location}")
        private String frontendLocation;

        @Override
        public void addViewControllers(ViewControllerRegistry reg) {
            reg.addViewController("/").setViewName("forward:/index.html");
            reg.addViewController("/{x:[\\w\\-]+}").setViewName("forward:/index.html");
        }

        @Override
        public void addResourceHandlers(ResourceHandlerRegistry registry) {
            registry.addResourceHandler("/**").addResourceLocations(frontendLocation);
        }

    }

This works fine as long as there is no server.servlet.context-path. When server.servlet.context-path is configured, it is being passed down to the frontend router as part of the URL. The solution would be not to forward context path to index.html. How can I achieve that?