Chrome DevTools Many browsers provide “DevTools” – a set of tools that are integrated with the browser that
developers can use to debug web apps and explore the performance of their pages. Google Chrome’s
DevTools make use of a protocol called the Chrome DevTools Protocol (or “CDP” for short).
As the name suggests, this is not designed for testing, nor to have a stable API, so functionality
is highly dependent on the version of the browser.
The WebDriver BiDirectional Protocol  is the next generation of the
W3C WebDriver protocol and aims to provide a stable API implemented by all browsers, but it’s not yet complete.
Until it is, Selenium provides access to
the CDP for those browsers that implement it (such as Google Chrome, or Microsoft Edge, and
Firefox), allowing you to enhance your tests in interesting ways. Some examples of what you can
do with it are given below.
There are three different ways to access Chrome DevTools in Selenium. If you look for other examples online,
you will likely see each of these mixed and matched.
The CDP Endpoint  was the first option available to users.
It only works for the most simple things (setting state, getting basic information), and you
have to know the “magic strings” for the domain and methods and key value pairs.
For basic requirements, this might be simpler than the other options. These methods are only temporarily supported. The CDP API  is an improvement on just using the endpoint because you can set
do things asynchronously. Instead of a String and a Map, you can access the supported classes,
methods and parameters in the code. These methods are also only temporarily supported. The BiDi API  option should be used whenever possible because it
abstracts away the implementation details entirely and will work with either CDP or WebDriver-BiDi
when Selenium moves away from CDP. Examples With Limited Value There are a number of commonly cited examples for using CDP that are of limited practical value.
Geo Location  — almost all sites use the IP address to determine physical location,
so setting an emulated geolocation rarely has the desired effect.Overriding Device Metrics  — Chrome provides a great API for setting Mobile Emulation 
in the Options classes, which is generally superior to attempting to do this with CDP.Check out the examples in these documents for ways to do additional useful things:
1 - Chrome DevTools Protocol Endpoint Google provides a /cdp/execute endpoint that can be accessed directly. Each Selenium binding provides a method that allows you to pass the CDP domain as a String, and the required parameters as a simple Map.
These methods will eventually be removed. It is recommended to use the WebDriver-BiDi  or WebDriver Bidi APIs 
methods where possible to ensure future compatibility.
Usage Generally you should prefer the use of the CDP API  over this approach,
but sometimes the syntax is cleaner or significantly more simple.
Limitations include:
It only works for use cases that are limited to setting or getting information;
any actual asynchronous interactions require another implementation You have to know the exactly correct “magic strings” for domains and keys It is possible that an update to Chrome will change the required parameters Examples Set Cookie An alternate implementation can be found at CDP API Set Cookie 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin     Map < String ,  Object >  cookie  =  new  HashMap <>(); 
     cookie . put ( "name" ,  "cheese" ); 
     cookie . put ( "value" ,  "gouda" ); 
     cookie . put ( "domain" ,  "www.selenium.dev" ); 
     cookie . put ( "secure" ,  true ); 
 
     (( HasCdp )  driver ). executeCdpCommand ( "Network.setCookie" ,  cookie );      cookie  =  { 'name' :  'cheese' , 
               'value' :  'gouda' , 
               'domain' :  'www.selenium.dev' , 
               'secure' :  True } 
 
     driver . execute_cdp_cmd ( 'Network.setCookie' ,  cookie )              var  cookie  =  new  Dictionary < string ,  object > 
             { 
                 {  "name" ,  "cheese"  }, 
                 {  "value" ,  "gouda"  }, 
                 {  "domain" ,  "www.selenium.dev"  }, 
                 {  "secure" ,  true  } 
             }; 
 
             (( ChromeDriver ) driver ). ExecuteCdpCommand ( "Network.setCookie" ,  cookie );  The CDP API Set Cookie  implementation should be preferred
    cookie  =  { name :  'cheese' , 
               value :  'gouda' , 
               domain :  'www.selenium.dev' , 
               secure :  true } 
 
     driver . execute_cdp ( 'Network.setCookie' ,  ** cookie )  An alternate implementation can be found at CDP API Performance Metrics 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin The CDP API Performance Metrics  implementation should be preferred
    (( HasCdp )  driver ). executeCdpCommand ( "Performance.enable" ,  new  HashMap <>()); 
 
     Map < String ,  Object >  response  = 
         (( HasCdp )  driver ). executeCdpCommand ( "Performance.getMetrics" ,  new  HashMap <>());      driver . execute_cdp_cmd ( 'Performance.enable' ,  {}) 
 
     metric_list  =  driver . execute_cdp_cmd ( 'Performance.getMetrics' ,  {})[ "metrics" ]              (( ChromeDriver ) driver ). ExecuteCdpCommand ( "Performance.enable" ,  emptyDictionary ); 
 
             Dictionary < string ,  object >  response  =  ( Dictionary < string ,  object >)(( ChromeDriver ) driver ) 
                 . ExecuteCdpCommand ( "Performance.getMetrics" ,  emptyDictionary );  The CDP API Performance Metrics  implementation should be preferred
    driver . execute_cdp ( 'Performance.enable' ) 
 
     metric_list  =  driver . execute_cdp ( 'Performance.getMetrics' ) [ 'metrics' ]  Basic authentication Alternate implementations can be found at CDP API Basic Authentication 
and BiDi API Basic Authentication 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin The BiDi API Basic Authentication  implementation should be preferred
    (( HasCdp )  driver ). executeCdpCommand ( "Network.enable" ,  new  HashMap <>()); 
 
     String  encodedAuth  =  Base64 . getEncoder (). encodeToString ( "admin:admin" . getBytes ()); 
     Map < String ,  Object >  headers  = 
         ImmutableMap . of ( "headers" ,  ImmutableMap . of ( "authorization" ,  "Basic "  +  encodedAuth )); 
 
     (( HasCdp )  driver ). executeCdpCommand ( "Network.setExtraHTTPHeaders" ,  headers );      driver . execute_cdp_cmd ( "Network.enable" ,  {}) 
 
     credentials  =  base64 . b64encode ( "admin:admin" . encode ()) . decode () 
     headers  =  { 'headers' :  { 'authorization' :  'Basic '  +  credentials }} 
 
     driver . execute_cdp_cmd ( 'Network.setExtraHTTPHeaders' ,  headers )              (( ChromeDriver ) driver ). ExecuteCdpCommand ( "Network.enable" ,  emptyDictionary ); 
             
             string  encodedAuth  =  Convert . ToBase64String ( Encoding . Default . GetBytes ( "admin:admin" )); 
             var  headers  =  new  Dictionary < string ,  object > 
             { 
                 {  "headers" ,  new  Dictionary < string ,  string >  {  {  "authorization" ,  "Basic "  +  encodedAuth  }  }  } 
             }; 
 
             (( ChromeDriver ) driver ). ExecuteCdpCommand ( "Network.setExtraHTTPHeaders" ,  headers );  The BiDi API Basic Authentication  implementation should be preferred
    driver . execute_cdp ( 'Network.enable' ) 
 
     credentials  =  Base64 . strict_encode64 ( 'admin:admin' ) 
     headers  =  { authorization :  "Basic  #{ credentials } " } 
 
     driver . execute_cdp ( 'Network.setExtraHTTPHeaders' ,  headers :  headers )  2 - Chrome DevTools Protocol API Each of the Selenium bindings dynamically generates classes and methods for the various CDP domains and features; these are tied to specific versions of Chrome.
While Selenium 4 provides direct access to the Chrome DevTools Protocol (CDP), these
methods will eventually be removed. It is recommended to use the WebDriver Bidi APIs 
methods where possible to ensure future compatibility.
Usage If your use case has been implemented by WebDriver Bidi  or
the BiDi API , you should use those implementations instead of this one.
Generally you should prefer this approach over executing with the CDP Endpoint ,
especially in Ruby.
Examples Set Cookie An alternate implementation can be found at CDP Endpoint Set Cookie 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin Because Java requires using all the parameters example, the Map approach used in
CDP Endpoint Set Cookie  might be more simple.
    devTools  =  (( HasDevTools )  driver ). getDevTools (); 
     devTools . createSession (); 
 
     devTools . send ( 
         Network . setCookie ( 
             "cheese" , 
             "gouda" , 
             Optional . empty (), 
             Optional . of ( "www.selenium.dev" ), 
             Optional . empty (), 
             Optional . of ( true ), 
             Optional . empty (), 
             Optional . empty (), 
             Optional . empty (), 
             Optional . empty (), 
             Optional . empty (), 
             Optional . empty (), 
             Optional . empty (), 
             Optional . empty ()));  Because Python requires using async methods for this example, the synchronous approach found in
CDP Endpoint Set Cookie  might be easier.
    async  with  driver . bidi_connection ()  as  connection : 
         execution  =  connection . devtools . network . set_cookie ( 
             name = "cheese" , 
             value = "gouda" , 
             domain = "www.selenium.dev" , 
             secure = True 
         ) 
 
         await  connection . session . execute ( execution )  Due to the added complexity in .NET of obtaining the domains and executing with awaits, the
CDP Endpoint Set Cookie  might be easier.
            var  session  =  (( IDevTools ) driver ). GetDevToolsSession (); 
             var  domains  =  session . GetVersionSpecificDomains < OpenQA . Selenium . DevTools . V118 . DevToolsSessionDomains >(); 
             await  domains . Network . Enable ( new  OpenQA . Selenium . DevTools . V118 . Network . EnableCommandSettings ()); 
 
             var  cookieCommandSettings  =  new  SetCookieCommandSettings 
             { 
                 Name  =  "cheese" , 
                 Value  =  "gouda" , 
                 Domain  =  "www.selenium.dev" , 
                 Secure  =  true 
             }; 
 
             await  domains . Network . SetCookie ( cookieCommandSettings );      driver . devtools . network . set_cookie ( name :  'cheese' , 
                                        value :  'gouda' , 
                                        domain :  'www.selenium.dev' , 
                                        secure :  true )  An alternate implementation can be found at CDP Endpoint Performance Metrics 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin     devTools  =  (( HasDevTools )  driver ). getDevTools (); 
     devTools . createSession (); 
     devTools . send ( Performance . enable ( Optional . empty ())); 
 
     List < Metric >  metricList  =  devTools . send ( Performance . getMetrics ());  Because Python requires using async methods for this example, the synchronous approach found in
CDP Endpoint Performance Metrics  might be easier.
    async  with  driver . bidi_connection ()  as  connection : 
         await  connection . session . execute ( connection . devtools . performance . enable ()) 
 
         metric_list  =  await  connection . session . execute ( connection . devtools . performance . get_metrics ())  Due to the added complexity in .NET of obtaining the domains and executing with awaits, the
CDP Endpoint Performance Metrics  might be easier.
            var  session  =  (( IDevTools ) driver ). GetDevToolsSession (); 
             var  domains  =  session . GetVersionSpecificDomains < OpenQA . Selenium . DevTools . V118 . DevToolsSessionDomains >(); 
             await  domains . Performance . Enable ( new  OpenQA . Selenium . DevTools . V118 . Performance . EnableCommandSettings ()); 
 
             var  metricsResponse  = 
                 await  session . SendCommand < GetMetricsCommandSettings ,  GetMetricsCommandResponse >( 
                     new  GetMetricsCommandSettings () 
                 );      driver . devtools . performance . enable 
 
     metric_list  =  driver . devtools . performance . get_metrics . dig ( 'result' ,  'metrics' )  Basic authentication Alternate implementations can be found at
CDP Endpoint Basic Authentication 
and BiDi API Basic Authentication 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin The BiDi API Basic Authentication  implementation should be preferred
    devTools  =  (( HasDevTools )  driver ). getDevTools (); 
     devTools . createSession (); 
     devTools . send ( Network . enable ( Optional . of ( 100000 ),  Optional . of ( 100000 ),  Optional . of ( 100000 ))); 
 
     String  encodedAuth  =  Base64 . getEncoder (). encodeToString ( "admin:admin" . getBytes ()); 
     Map < String ,  Object >  headers  =  ImmutableMap . of ( "Authorization" ,  "Basic "  +  encodedAuth ); 
 
     devTools . send ( Network . setExtraHTTPHeaders ( new  Headers ( headers )));  Because Python requires using async methods for this example, the synchronous approach found in
CDP Endpoint Basic Authentication  might be easier.
    async  with  driver . bidi_connection ()  as  connection : 
         await  connection . session . execute ( connection . devtools . network . enable ()) 
 
         credentials  =  base64 . b64encode ( "admin:admin" . encode ()) . decode () 
         auth  =  { 'authorization' :  'Basic '  +  credentials } 
 
         await  connection . session . execute ( connection . devtools . network . set_extra_http_headers ( Headers ( auth )))  Due to the added complexity in .NET of obtaining the domains and executing with awaits, the
CDP Endpoint Basic Authentication  might be easier.
            var  session  =  (( IDevTools ) driver ). GetDevToolsSession (); 
             var  domains  =  session . GetVersionSpecificDomains < OpenQA . Selenium . DevTools . V118 . DevToolsSessionDomains >(); 
             await  domains . Network . Enable ( new  OpenQA . Selenium . DevTools . V118 . Network . EnableCommandSettings ()); 
 
             var  encodedAuth  =  Convert . ToBase64String ( Encoding . Default . GetBytes ( "admin:admin" )); 
             var  headerSettings  =  new  SetExtraHTTPHeadersCommandSettings 
             { 
                 Headers  =  new  Headers () 
                 { 
                     {  "authorization" ,  "Basic "  +  encodedAuth  } 
                 } 
             }; 
 
             await  domains . Network . SetExtraHTTPHeaders ( headerSettings );  The BiDi API Basic Authentication  implementation should be preferred
    driver . devtools . network . enable 
 
     credentials  =  Base64 . strict_encode64 ( 'admin:admin' ) 
 
     driver . devtools . network . set_extra_http_headers ( headers :  { authorization :  "Basic  #{ credentials } " })  Console logs Because reading console logs requires setting an event listener,
this cannot be done with a CDP Endpoint implementation
Alternate implementations can be found at
BiDi API Console logs and errors 
and WebDriver BiDi Console logs 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin Use the WebDriver BiDi Console logs  implementation
    DevTools  devTools  =  (( HasDevTools )  driver ). getDevTools (); 
     devTools . createSession (); 
     devTools . send ( Runtime . enable ()); 
 
     CopyOnWriteArrayList < String >  logs  =  new  CopyOnWriteArrayList <>(); 
     devTools . addListener ( 
         Runtime . consoleAPICalled (), 
         event  ->  logs . add (( String )  event . getArgs (). get ( 0 ). getValue (). orElse ( "" )));  The BiDi API Console logs and errors  implementation should be preferred
    driver . devtools . runtime . enable 
 
     logs  =  [] 
     driver . devtools . runtime . on ( :console_api_called )  do  | params | 
       logs  <<  params [ 'args' ]. first [ 'value' ] 
     end  JavaScript exceptions Similar to console logs, but this listens for actual javascript exceptions not just logged errors
Alternate implementations can be found at
BiDi API JavaScript exceptions 
and WebDriver BiDi JavaScript exceptions 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin Use the WebDriver BiDi JavaScript exceptions  implementation
    DevTools  devTools  =  (( HasDevTools )  driver ). getDevTools (); 
     devTools . createSession (); 
     devTools . send ( Runtime . enable ()); 
 
     CopyOnWriteArrayList < JavascriptException >  errors  =  new  CopyOnWriteArrayList <>(); 
     devTools . getDomains (). events (). addJavascriptExceptionListener ( errors :: add );  Download complete Wait for a download to finish before continuing.
Because getting download status requires setting a listener, this cannot be done with a CDP Endpoint implementation.
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin     devTools  =  (( HasDevTools )  driver ). getDevTools (); 
     devTools . createSession (); 
     devTools . send ( 
         Browser . setDownloadBehavior ( 
             Browser . SetDownloadBehaviorBehavior . ALLOWANDNAME , 
             Optional . empty (), 
             Optional . of ( "" ), 
             Optional . of ( true ))); 
 
     AtomicBoolean  completed  =  new  AtomicBoolean ( false ); 
     devTools . addListener ( 
         Browser . downloadProgress (), 
         e  ->  completed . set ( Objects . equals ( e . getState (). toString (),  "completed" )));      driver . devtools . browser . set_download_behavior ( behavior :  'allow' , 
                                                   download_path :  '' , 
                                                   events_enabled :  true ) 
 
     driver . devtools . browser . on ( :download_progress )  do  | progress | 
       @completed  =  progress [ 'state' ]  ==  'completed' 
     end  3 - Chrome Devtools Protocol with BiDi API These examples are currently implemented with CDP, but the same code should work when the functionality is re-implemented with WebDriver-BiDi.
Usage The following list of APIs will be growing as the Selenium
project works through supporting real world use cases. If there
is additional functionality you’d like to see, please raise a
feature request .
As these examples are re-implemented with the WebDriver-Bidi  protocol, they will
be moved to the WebDriver Bidi  pages.
Examples Basic authentication Some applications make use of browser authentication to secure pages.
It used to be common to handle them in the URL, but browser stopped supporting this.
With BiDi, you can now provide the credentials when necessary
Alternate implementations can be found at
CDP Endpoint Basic Authentication 
and CDP API Basic Authentication 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin     Predicate < URI >  uriPredicate  =  uri  ->  uri . toString (). contains ( "herokuapp.com" ); 
     Supplier < Credentials >  authentication  =  UsernameAndPassword . of ( "admin" ,  "admin" ); 
 
     (( HasAuthentication )  driver ). register ( uriPredicate ,  authentication );              var  handler  =  new  NetworkAuthenticationHandler () 
             { 
                 UriMatcher  =  uri  =>  uri . AbsoluteUri . Contains ( "herokuapp" ), 
                 Credentials  =  new  PasswordCredentials ( "admin" ,  "admin" ) 
             }; 
 
             var  networkInterceptor  =  driver . Manage (). Network ; 
             networkInterceptor . AddAuthenticationHandler ( handler ); 
 
             await  networkInterceptor . StartMonitoring ();      driver . register ( username :  'admin' , 
                     password :  'admin' , 
                     uri :  /herokuapp/ )  Move Code 
const  { Builder }  =  require ( 'selenium-webdriver' ); 
 ( async  function  example ()  { 
  try  { 
     let  driver  =  await  new  Builder () 
       . forBrowser ( 'chrome' ) 
       . build (); 
 
     const  pageCdpConnection  =  await  driver . createCDPConnection ( 'page' ); 
     await  driver . register ( 'username' ,  'password' ,  pageCdpConnection ); 
     await  driver . get ( 'https://the-internet.herokuapp.com/basic_auth' ); 
     await  driver . quit (); 
   } catch  ( e ){ 
     console . log ( e ) 
   } 
 }()) 
Move Code 
val  uriPredicate  =  Predicate  {  uri :  URI  -> 
        uri . host . contains ( "your-domain.com" ) 
     } 
 ( driver  as  HasAuthentication ). register ( uriPredicate ,  UsernameAndPassword . of ( "admin" ,  "password" )) 
driver . get ( "https://your-domain.com/login" ) 
Pin scripts This can be especially useful when executing on a remote server. For example,
whenever you check the visibility of an element, or whenever you use
the classic get attribute method, Selenium is sending the contents of a js file
to the script execution endpoint. These files are each about 50kB, which adds up.
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin             var  key  =  await  new  JavaScriptEngine ( driver ). PinScript ( "return arguments;" ); 
 
             var  arguments  =  (( WebDriver ) driver ). ExecuteScript ( key ,  1 ,  true ,  element );      key  =  driver . pin_script ( 'return arguments;' ) 
     arguments  =  driver . execute_script ( key ,  1 ,  true ,  element )  Mutation observation Mutation Observation is the ability to capture events via
WebDriver BiDi when there are DOM mutations on a specific
element in the DOM.
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin     CopyOnWriteArrayList < WebElement >  mutations  =  new  CopyOnWriteArrayList <>(); 
     (( HasLogEvents )  driver ). onLogEvent ( domMutation ( e  ->  mutations . add ( e . getElement ())));      async  with  driver . bidi_connection ()  as  session : 
         log  =  Log ( driver ,  session ) 
             var  mutations  =  new  List < IWebElement >(); 
             using  IJavaScriptEngine  monitor  =  new  JavaScriptEngine ( driver ); 
             monitor . DomMutated  +=  ( _ ,  e )  => 
             { 
                 var  locator  =  By . CssSelector ( $"*[data-__webdriver_id='{e.AttributeData.TargetId}']" ); 
                 mutations . Add ( driver . FindElement ( locator )); 
             }; 
 
             await  monitor . StartEventMonitoring (); 
             await  monitor . EnableDomMutationMonitoring ();      mutations  =  [] 
     driver . on_log_event ( :mutation )  {  | mutation |  mutations  <<  mutation . element  }  Move Code 
const  { Builder ,  until }  =  require ( 'selenium-webdriver' ); 
const  assert  =  require ( "assert" ); 
 ( async  function  example ()  { 
  try  { 
     let  driver  =  await  new  Builder () 
       . forBrowser ( 'chrome' ) 
       . build (); 
 
     const  cdpConnection  =  await  driver . createCDPConnection ( 'page' ); 
     await  driver . logMutationEvents ( cdpConnection ,  event  =>  { 
       assert . deepStrictEqual ( event [ 'attribute_name' ],  'style' ); 
       assert . deepStrictEqual ( event [ 'current_value' ],  "" ); 
       assert . deepStrictEqual ( event [ 'old_value' ],  "display:none;" ); 
     }); 
 
     await  driver . get ( 'dynamic.html' ); 
     await  driver . findElement ({ id :  'reveal' }). click (); 
     let  revealed  =  driver . findElement ({ id :  'revealed' }); 
     await  driver . wait ( until . elementIsVisible ( revealed ),  5000 ); 
     await  driver . quit (); 
   } catch  ( e ){ 
     console . log ( e ) 
   } 
 }()) 
Console logs and errors Listen to the console.log events and register callbacks to process the event.
CDP API Console logs 
and WebDriver BiDi Console logs 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin Use the WebDriver BiDi Console logs  implementation. HasLogEvents
will likely end up deprecated because it does not implement Closeable.
    CopyOnWriteArrayList < String >  messages  =  new  CopyOnWriteArrayList <>(); 
     (( HasLogEvents )  driver ). onLogEvent ( consoleEvent ( e  ->  messages . add ( e . getMessages (). get ( 0 ))));      async  with  driver . bidi_connection ()  as  session : 
         log  =  Log ( driver ,  session ) 
 
         async  with  log . add_listener ( Console . ALL )  as  messages :              using  IJavaScriptEngine  monitor  =  new  JavaScriptEngine ( driver ); 
             var  messages  =  new  List < string >(); 
             monitor . JavaScriptConsoleApiCalled  +=  ( _ ,  e )  => 
             { 
                 messages . Add ( e . MessageContent ); 
             }; 
 
             await  monitor . StartEventMonitoring ();      logs  =  [] 
     driver . on_log_event ( :console )  {  | log |  logs  <<  log . args . first  }  Move Code 
const  { Builder }  =  require ( 'selenium-webdriver' ); 
( async  ()  =>  { 
  try  { 
     let  driver  =  new  Builder () 
       . forBrowser ( 'chrome' ) 
       . build (); 
 
     const  cdpConnection  =  await  driver . createCDPConnection ( 'page' ); 
     await  driver . onLogEvent ( cdpConnection ,  function  ( event )  { 
       console . log ( event [ 'args' ][ 0 ][ 'value' ]); 
     }); 
     await  driver . executeScript ( 'console.log("here")' ); 
     await  driver . quit (); 
   } catch  ( e ){ 
     console . log ( e ); 
   } 
 })() 
Move Code 
fun  kotlinConsoleLogExample ()  { 
    val  driver  =  ChromeDriver () 
     val  devTools  =  driver . devTools 
     devTools . createSession () 
 
     val  logConsole  =  {  c :  ConsoleEvent  ->  print ( "Console log message is: "  +  c . messages )} 
     devTools . domains . events (). addConsoleListener ( logConsole ) 
 
     driver . get ( "https://www.google.com" ) 
 
     val  executor  =  driver  as  JavascriptExecutor 
     executor . executeScript ( "console.log('Hello World')" ) 
 
     val  input  =  driver . findElement ( By . name ( "q" )) 
     input . sendKeys ( "Selenium 4" ) 
     input . sendKeys ( Keys . RETURN ) 
     driver . quit () 
 } 
JavaScript exceptions Listen to the JS Exceptions
and register callbacks to process the exception details.
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin     async  with  driver . bidi_connection ()  as  session : 
         log  =  Log ( driver ,  session ) 
 
         async  with  log . add_js_error_listener ()  as  messages :              using  IJavaScriptEngine  monitor  =  new  JavaScriptEngine ( driver ); 
             var  messages  =  new  List < string >(); 
             monitor . JavaScriptExceptionThrown  +=  ( _ ,  e )  => 
             { 
                 messages . Add ( e . Message ); 
             }; 
 
             await  monitor . StartEventMonitoring ();      exceptions  =  [] 
     driver . on_log_event ( :exception )  {  | exception |  exceptions  <<  exception  }  Network Interception Both requests and responses can be recorded or transformed.
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin     CopyOnWriteArrayList < String >  contentType  =  new  CopyOnWriteArrayList <>(); 
 
     try  ( NetworkInterceptor  ignored  = 
         new  NetworkInterceptor ( 
             driver , 
             ( Filter ) 
                 next  -> 
                     req  ->  { 
                       HttpResponse  res  =  next . execute ( req ); 
                       contentType . add ( res . getHeader ( "Content-Type" )); 
                       return  res ; 
                     }))  {              var  contentType  =  new  List < string >(); 
 
             INetwork  networkInterceptor  =  driver . Manage (). Network ; 
             networkInterceptor . NetworkResponseReceived  +=  ( _ ,  e )   => 
             { 
                 contentType . Add ( e . ResponseHeaders [ "content-type" ]); 
             }; 
 
             await  networkInterceptor . StartMonitoring ();      content_type  =  [] 
     driver . intercept  do  | request ,  & continue | 
       continue . call ( request )  do  | response | 
         content_type  <<  response . headers [ 'content-type' ] 
       end 
     end  
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin     try  ( NetworkInterceptor  ignored  = 
         new  NetworkInterceptor ( 
             driver , 
             Route . matching ( req  ->  true ) 
                 . to ( 
                     ()  -> 
                         req  -> 
                             new  HttpResponse () 
                                 . setStatus ( 200 ) 
                                 . addHeader ( "Content-Type" ,  MediaType . HTML_UTF_8 . toString ()) 
                                 . setContent ( Contents . utf8String ( "Creamy, delicious cheese!" )))))  {              var  handler  =  new  NetworkResponseHandler () 
             { 
                 ResponseMatcher  =  _  =>  true , 
                 ResponseTransformer  =  _  =>  new  HttpResponseData 
                 { 
                     StatusCode  =  200 , 
                     Body  =  "Creamy, delicious cheese!" 
                 } 
             }; 
 
             INetwork  networkInterceptor  =  driver . Manage (). Network ; 
             networkInterceptor . AddResponseHandler ( handler ); 
 
             await  networkInterceptor . StartMonitoring ();      driver . intercept  do  | request ,  & continue | 
       continue . call ( request )  do  | response | 
         response . body  =  'Creamy, delicious cheese!'  if  request . url . include? ( 'blank' ) 
       end 
     end  Move Code 
const  connection  =  await  driver . createCDPConnection ( 'page' ) 
let  url  =  fileServer . whereIs ( "/cheese" ) 
let  httpResponse  =  new  HttpResponse ( url ) 
httpResponse . addHeaders ( "Content-Type" ,  "UTF-8" ) 
httpResponse . body  =  "sausages" 
await  driver . onIntercept ( connection ,  httpResponse ,  async  function  ()  { 
  let  body  =  await  driver . getPageSource () 
   assert . strictEqual ( body . includes ( "sausages" ),  true ,  `Body contains:  ${ body } ` ) 
 }) 
driver . get ( url ) 
Move Code 
val  driver  =  ChromeDriver () 
val  interceptor  =  new  NetworkInterceptor ( 
      driver , 
       Route . matching ( req  ->  true ) 
         . to (()  ->  req  ->  new  HttpResponse () 
           . setStatus ( 200 ) 
           . addHeader ( "Content-Type" ,  MediaType . HTML_UTF_8 . toString ()) 
           . setContent ( utf8String ( "Creamy, delicious cheese!" )))) 
 
     driver . get ( appServer . whereIs ( "/cheese" )) 
 
     String  source  =  driver . getPageSource () 
 Request interception 
Java 
Python 
CSharp 
Ruby 
JavaScript 
Kotlin             var  handler  =  new  NetworkRequestHandler 
             { 
                 RequestMatcher  =  request  =>  request . Url . Contains ( "one.js" ), 
                 RequestTransformer  =  request  => 
                 { 
                     request . Url  =  request . Url . Replace ( "one" ,  "two" ); 
 
                     return  request ; 
                 } 
             }; 
 
             INetwork  networkInterceptor  =  driver . Manage (). Network ; 
             networkInterceptor . AddRequestHandler ( handler ); 
 
             await  networkInterceptor . StartMonitoring ();      driver . intercept  do  | request ,  & continue | 
       uri  =  URI ( request . url ) 
       request . url  =  uri . to_s . gsub ( 'one' ,  'two' )  if  uri . path &. end_with? ( 'one.js' ) 
       continue . call ( request ) 
     end