开启Spring Security认证后外部CSS文件无法加载的问题求助

配置Spring Security认证规则后，页面的外部CSS、JS及图片等静态资源无法正常加载；但将所有请求设置为anyRequest().permitAll()允许访问时，静态资源可正常工作。

问题复现代码 #

存在问题的SecurityConfig配置 #

@EnableWebSecurity
@Configuration
class SecurityConfig {

    @Bean
    fun security(http:HttpSecurity):SecurityFilterChain{
        http
            .formLogin()
                .loginPage("/")
                .failureUrl("/")
                .and()
            .logout()
                .logoutSuccessUrl("/")
                .and()
            .authorizeHttpRequests()
                .requestMatchers("/","/about_us").permitAll()
                .anyRequest().authenticated()
        return http.build();
    }
}

前端HTML页面 #

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
  <meta charset="UTF-8">
  <title>BigBroHelp</title>
  <link rel="stylesheet" type="text/css" href="../../static/css/final_form.css">
  <link th:href="@{/css/start_page/final_form.css}" rel="stylesheet">
  <link th:href="@{https://fonts.googleapis.com/css2?family=Jost:wght@500&display=swap}" rel="stylesheet">
  <link th:href="@{/img/ответы_нейро_бошка.png}" rel="icon" type="image/png" style="width: 1000px">
  <script th:src="@{/js/start_page/validation_counter.js}"></script>
  
</head>
<body id="body">


<div class="main">
  <input type="checkbox" id="chk" aria-hidden="true">

  <div class="signup">
    <form>
      <label for="chk" aria-hidden="true" id="reg_label">Регистрация</label>
      <p id="count">0</p>
      <input type="text" name="txt" placeholder="Логин" required="" id="reg_input_login" onclick="count()">
<!--      <input type="email" name="email" placeholder="Почта" required="">-->
      <input type="password" name="pswd" placeholder="Пароль" required="">
      <button onclick="count()">Зарегистрироваться</button>
    </form>
  </div>

  <div class="login">
    <form>
      <label for="chk" aria-hidden="true">Войти</label>
      <input type="email" name="email" placeholder="Логин" required="">
      <input type="password" name="pswd" placeholder="Пароль" required="">
      <button>Войти</button>
    </form>
  </div>
</div>

<div class="bigBro">
  <div class="modal">
    <h1>
      Big Bro Help<br>
    </h1>

    <a class="btn" id="about_us" th:href="@{/about_us}">О проекте </a><br>

  </div>
</div>

</body>
</html>

正常工作的SecurityConfig配置 #

@EnableWebSecurity
@Configuration
class SecurityConfig {

    @Bean
    fun security(http:HttpSecurity):SecurityFilterChain{
        http
            .authorizeHttpRequests()
                .anyRequest().permitAll()
        return http.build();
    }
}

相关版本信息 #

• Spring Boot版本：3.0.2（Spring Security 6.0.1）
• Thymeleaf版本：3.1.1

效果截图 #

页面显示效果截图：

CSS加载失败截图：

内容的提问来源于stack exchange，提问作者de6igz