Suggested optimization: LoopbackIpRedirectFilter

\spring-security-samples\servlet\spring-boot\java\oauth2\login\src\main\java\example\filter\LoopbackIpRedirectFilter.java

Should not be configured：

if (request.getServerName().equals("localhost") && request.getHeader("host") != null) {
UriComponents uri = UriComponentsBuilder.fromHttpRequest(new ServletServerHttpRequest(request))
.host("127.0.0.1").build();
response.sendRedirect(uri.toUriString());
return;
}

In the oauth2 of Google login and GitHub login, there will be a prompt error that the callback address is different from the callback address configured by the application, and an error will be reported.

Because Google login does not allow setting the callback URL of 127.0.0.1, it needs a domain name, similar to localhost, but LoopbackIpRedirectFilter will change it to 127.0.0.1

Start with spring-security-samples/servlet/spring-boot/java/oauth2/login/src/main/java/example/filter/LoopbackIpRedirectFilter.java and inspect where it is configured in the OAuth2 login sample. Verify the Google and GitHub callback behavior, then ensure localhost callback URLs are not rewritten to 127.0.0.1.