If you have more than one copy of React DevTools installed and enabled (e.g. the version in the Chrome store and a locally built version) they can interfere with each other.

DevTools should detect this case and warn by showing a dialog in the DevTools UI and/or by logging to the console.

Note that we _should not warn_ if a related tool like Fast Refresh is present, only another copy of DevTools.
<FetchFileWithCachingContext.Provider
                      value={fetchFileWithCaching || null}>
                      <TreeContextController>
                        <ProfilerContextController>
                          <SchedulingProfilerContextController>
                            <ThemeProvider>
                              <div
                                className={styles.DevTools}
                                ref={devToolsRef}
                                data-react-devtools-portal-root={true}>
                                {showTabBar && (
                                  <div className={styles.TabBar}>
                                    <ReactLogo />
                                    <span className={styles.DevToolsVersion}>
                                      {process.env.DEVTOOLS_VERSION}
                                    </span>
                                    <div className={styles.Spacer} />
                                    <TabBar
                                      currentTab={tab}
                                      id="DevTools"
                                      selectTab={selectTab}
                                      tabs={tabs}
                                      type="navigation"
                                    />
                                  </div>
                                )}
                                <div
                                  className={styles.TabContent}
                                  hidden={tab !== 'components'}>
                                  <Components