code: // Licensed to the Software Freedom Conservancy (SFC) under one
  // or more contributor license agreements.  See the NOTICE file
  // distributed with this work for additional information
  // regarding copyright ownership.  The SFC licenses this file
  // to you under the Apache License, Version 2.0 (the
  // "License"); you may not use this file except in compliance
  // with the License.  You may obtain a copy of the License at
  //
  //   http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing,
  // software distributed under the License is distributed on an
  // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  // KIND, either express or implied.  See the License for the
  // specific language governing permissions and limitations
  // under the License.
  
  package org.openqa.selenium.devtools;
  
  import static org.assertj.core.api.Assumptions.assumeThat;
  import static org.junit.jupiter.api.Assumptions.assumeTrue;
  import static org.openqa.selenium.testing.TestUtilities.isFirefox;
  import static org.openqa.selenium.testing.TestUtilities.isFirefoxVersionOlderThan;
  
  import org.junit.jupiter.api.BeforeEach;
  import org.openqa.selenium.testing.JupiterTestBase;
  
  public abstract class DevToolsTestBase extends JupiterTestBase {
  
    protected DevTools devTools;
  
    @BeforeEach
    public void setUp() {
      assumeThat(driver).isInstanceOf(HasDevTools.class);
      assumeThat(isFirefoxVersionOlderThan(87, driver)).isFalse();
  
      devTools = ((HasDevTools) driver).getDevTools();
      devTools.createSessionIfThereIsNotOne(driver.getWindowHandle());
  
      try {
        devTools.clearListeners();
      } catch (DevToolsException e) {
        if (isFirefox(driver)) {
          assumeTrue(
              false, "Unable to clear listeners on Firefox because Fetch domain is not implemented");
        }
        throw e;
      }
    }
  }
  