RequestCacheConfigurer default request matcher doesn't allow saving POST requests when csrf is enabled

Summary

In a web application with Spring Security 4.2.x, RequestCacheConfigurer configures a default request matcher that doesn't allow saving POST requests when csrf is enabled.

Actual Behavior

When we submit a POST request against a secured endpoint the application redirects to the login page. After successful login the original POST request isn't restored so the invocation fails.

Expected Behavior

The original POST request is restored.

Configuration

I'm relying on Spring Security default configurations for the request cache. The key part is here RequestCacheConfigurer :

	private RequestMatcher createDefaultSavedRequestMatcher(H http) {
                ...
                if (isCsrfEnabled) {
			RequestMatcher getRequests = new AntPathRequestMatcher("/**", "GET");
			matchers.add(0, getRequests);
		}

If csrf is enabled only get requests will be cached.

Is there any security related reason why this matcher isn't supporting POST invocations?

Version

4.2.12

Start in RequestCacheConfigurer, specifically createDefaultSavedRequestMatcher, and inspect how the CSRF-enabled matcher handles POST requests. Reproduce a secured POST followed by login using the default request-cache configuration. Done means the original POST request is restored after successful login.