Check if user is using IE

I am calling a function like the one below by click on divs with a certain class.

Is there a way I can check when starting the function if a user is using Internet Explorer and abort / cancel it if they are using other browsers so that it only runs for IE users ? The users here would all be on IE8 or higher versions so I would not need to cover IE7 and lower versions.

If I could tell which browser they are using that would be great but is not required.

Example function:

$('.myClass').on('click', function(event)
{
    // my function
});

It's several years later, and the Edge browser now uses Chromium as its rendering engine.
Checking for IE 11 is still a thing, sadly.

Here is a more straightforward approach, as ancient versions of IE should be gone.

if (window.document.documentMode) {
  // Do IE stuff
}

---

Here is my old answer (2014):

In Edge the User Agent String has changed.

/**
 * detect IEEdge
 * returns version of IE/Edge or false, if browser is not a Microsoft browser
 */
function detectIEEdge() {
	var ua = window.navigator.userAgent;

	var msie = ua.indexOf('MSIE ');
	if (msie > 0) {
		// IE 10 or older => return version number
		return parseInt(ua.substring(msie + 5, ua.indexOf('.', msie)), 10);
	}

	var trident = ua.indexOf('Trident/');
	if (trident > 0) {
		// IE 11 => return version number
		var rv = ua.indexOf('rv:');
		return parseInt(ua.substring(rv + 3, ua.indexOf('.', rv)), 10);
	}

    var edge = ua.indexOf('Edge/');
    if (edge > 0) {
       // Edge => return version number
       return parseInt(ua.substring(edge + 5, ua.indexOf('.', edge)), 10);
    }

	// other browser
	return false;
}

Sample usage:

alert('IEEdge ' + detectIEEdge());

Default string of IE 10:

Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; Trident/6.0)

Default string of IE 11:

Mozilla/5.0 (Windows NT 6.3; Trident/7.0; rv:11.0) like Gecko 

Default string of Edge 12:

Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.71 Safari/537.36 Edge/12.0 

Default string of Edge 13 (thx @DrCord):

Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2486.0 Safari/537.36 Edge/13.10586 

Default string of Edge 14:

Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2486.0 Safari/537.36 Edge/14.14300 

Default string of Edge 15:

Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36 Edge/15.15063 

Default string of Edge 16:

Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36 Edge/16.16299 

Default string of Edge 17:

Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.140 Safari/537.36 Edge/17.17134 

Default string of Edge 18 (Insider preview):

Mozilla/5.0 (Windows NT 10.0; Win64; x64; ServiceUI 14) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.140 Safari/537.36 Edge/18.17730 

Test at CodePen:

http://codepen.io/gapcode/pen/vEJNZN

Use below JavaScript method :

function msieversion() 
{
	var ua = window.navigator.userAgent;
	var msie = ua.indexOf("MSIE ");

	if (msie > 0) // If Internet Explorer, return version number
	{
		alert(parseInt(ua.substring(msie + 5, ua.indexOf(".", msie))));
	}
	else  // If another browser, return 0
	{
		alert('otherbrowser');
	}

	return false;
}

You may find the details on below Microsoft support site :

How to determine browser version from script

Update : (IE 11 support)

function msieversion() {

	var ua = window.navigator.userAgent;
	var msie = ua.indexOf("MSIE ");

	if (msie > 0 || !!navigator.userAgent.match(/Trident.*rv\:11\./))  // If Internet Explorer, return version number
	{
		alert(parseInt(ua.substring(msie + 5, ua.indexOf(".", msie))));
	}
	else  // If another browser, return 0
	{
		alert('otherbrowser');
	}
	
	return false;
}

If all you want to know is if the browser is IE or not, you can do this:

var isIE = false;
var ua = window.navigator.userAgent;
var old_ie = ua.indexOf('MSIE ');
var new_ie = ua.indexOf('Trident/');

if ((old_ie > -1) || (new_ie > -1)) {
	isIE = true;
}

if ( isIE ) {
	//IE specific code goes here
}

Update 1: A better method

I recommend this now. It is still very readable and is far less code :)

var ua = window.navigator.userAgent;
var isIE = /MSIE|Trident/.test(ua);

if ( isIE ) {
  //IE specific code goes here
}

Thanks to JohnnyFun in the comments for the shortened answer :)

Update 2: Testing for IE in CSS

Firstly, if you can, you should use @supports statements instead of JS for checking if a browser supports a certain CSS feature.

.element {
  /* styles for all browsers */
}

@supports (display: grid) {
  .element {
    /* styles for browsers that support display: grid */
  }
}

(Note that IE doesn't support @supports at all and will ignore any styles placed inside an @supports statement.)

If the issue can't be resolved with @supports then you can do this:

// JS

var ua = window.navigator.userAgent;
var isIE = /MSIE|Trident/.test(ua);

if ( isIE ) {
  document.documentElement.classList.add('ie')
}

/* CSS */

.element {
  /* styles that apply everywhere */
}

.ie .element {
  /* styles that only apply in IE */
}

(Note: classList is relatively new to JS and I think, out of the IE browsers, it only works in IE11. Possibly also IE10.)

If you are using SCSS (Sass) in your project, this can be simplified to:

/* SCSS (Sass) */

.element {
  /* styles that apply everywhere */

  .ie & {
    /* styles that only apply in IE */
  }
}

Update 3: Adding Microsoft Edge (not recommended)

If you also want to add Microsoft Edge into the list, you can do the following. However I do not recommend it as Edge is a much more competent browser than IE.

var ua = window.navigator.userAgent;
var isIE = /MSIE|Trident|Edge\//.test(ua);

if ( isIE ) {
  //IE & Edge specific code goes here
}

This returns true for any version of Internet Explorer:

function isIE(userAgent) {
  userAgent = userAgent || navigator.userAgent;
  return userAgent.indexOf("MSIE ") > -1 || userAgent.indexOf("Trident/") > -1 || userAgent.indexOf("Edge/") > -1;
}

The userAgent parameter is optional and it defaults to the browser's user agent.

You can use the navigator object to detect user-navigator, you don't need jquery for it, the 4 comments below are already included so this snippet works as expected

if (/MSIE (\d+\.\d+);/.test(navigator.userAgent) || navigator.userAgent.indexOf("Trident/") > -1 ){ 
 // Do stuff with Internet-Exploders ... :)
}

http://www.javascriptkit.com/javatutors/navigator.shtml

This is how the Angularjs team is doing it (v 1.6.5):

var msie, // holds major version number for IE, or NaN if UA is not IE.

// Support: IE 9-11 only
/**
 * documentMode is an IE-only property
 * http://msdn.microsoft.com/en-us/library/ie/cc196988(v=vs.85).aspx
 */
msie = window.document.documentMode;

Then there are several lines of code scattered throughout using it as a number such as

if (event === 'input' && msie <= 11) return false;

and

if (enabled && msie < 8) {

You can simply do this:

var isIE = window.document.documentMode ? true : false; // this variable will hold if the current browser is IE

I know the question is old but if someone scrolled that far they can see the simple answer :)

Method 01:
$.browser was deprecated in jQuery version 1.3 and removed in 1.9

if ( $.browser.msie) {
  alert( "Hello! This is IE." );
}

Method 02:
Using Conditional Comments

<!--[if gte IE 8]>
<p>You're using a recent version of Internet Explorer.</p>
<![endif]-->

<!--[if lt IE 7]>
<p>Hm. You should upgrade your copy of Internet Explorer.</p>
<![endif]-->

<![if !IE]>
<p>You're not using Internet Explorer.</p>
<![endif]>

Method 03:

 /**
 * Returns the version of Internet Explorer or a -1
 * (indicating the use of another browser).
 */
function getInternetExplorerVersion()
{
    var rv = -1; // Return value assumes failure.

    if (navigator.appName == 'Microsoft Internet Explorer')
    {
        var ua = navigator.userAgent;
        var re  = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");
        if (re.exec(ua) != null)
            rv = parseFloat( RegExp.$1 );
    }

    return rv;
}

function checkVersion()
{
    var msg = "You're not using Internet Explorer.";
    var ver = getInternetExplorerVersion();

    if ( ver > -1 )
    {
        if ( ver >= 8.0 ) 
            msg = "You're using a recent copy of Internet Explorer."
        else
            msg = "You should upgrade your copy of Internet Explorer.";
    }

    alert( msg );
}

Method 04:
Use JavaScript/Manual Detection

/*
     Internet Explorer sniffer code to add class to body tag for IE version.
     Can be removed if your using something like Modernizr.
 */
 var ie = (function ()
 {
 
     var undef,
     v = 3,
         div = document.createElement('div'),
         all = div.getElementsByTagName('i');
 
     while (
     div.innerHTML = '<!--[if gt IE ' + (++v) + ']><i></i>< ![endif]-->',
     all[0]);
 
     //append class to body for use with browser support
     if (v > 4)
     {
         $('body').addClass('ie' + v);
     }
 
 }());

Reference Link

Using the answers above; simple & condensed returning Boolean:

var isIE = /(MSIE|Trident\/|Edge\/)/i.test(navigator.userAgent);

I just wanted to check if the browser was IE11 or older, because well, they're crap.

function isCrappyIE() {
    var ua = window.navigator.userAgent;
    var crappyIE = false;
    var msie = ua.indexOf('MSIE ');
    if (msie > 0) {// IE 10 or older => return version number        
        crappyIE = true;
    }
    var trident = ua.indexOf('Trident/');
    if (trident > 0) {// IE 11 => return version number        
        crappyIE = true;
    }
    return crappyIE;
}	

if(!isCrappyIE()){console.table('not a crappy browser);}

function detectIE() {
    var ua = window.navigator.userAgent;
    var ie = ua.search(/(MSIE|Trident|Edge)/);

    return ie > -1;
}

Using modernizr

Modernizr.addTest('ie', function () {
    var ua = window.navigator.userAgent;
    var msie = ua.indexOf('MSIE ') > 0;
    var ie11 = ua.indexOf('Trident/') > 0;
    var ie12 = ua.indexOf('Edge/') > 0;
    return msie || ie11 || ie12;
});

Or this really short version, returns true if the browsers is Internet Explorer:

function isIe() {
    return window.navigator.userAgent.indexOf("MSIE ") > 0
        || !!navigator.userAgent.match(/Trident.*rv\:11\./);
}

Yet another simple (yet human readable) function to detect if the browser is IE or not (ignoring Edge, which isn't bad at all):

function isIE() {
  var ua = window.navigator.userAgent;
  var msie = ua.indexOf('MSIE '); // IE 10 or older
  var trident = ua.indexOf('Trident/'); //IE 11

  return (msie > 0 || trident > 0);
}

Try this if you are using jquery version >=1.9,

var browser;
jQuery.uaMatch = function (ua) {
    ua = ua.toLowerCase();

    var match = /(chrome)[ \/]([\w.]+)/.exec(ua) ||
        /(webkit)[ \/]([\w.]+)/.exec(ua) ||
        /(opera)(?:.*version|)[ \/]([\w.]+)/.exec(ua) ||
        /(msie) ([\w.]+)/.exec(ua) || 
        ua.indexOf("compatible") < 0 && /(mozilla)(?:.*? rv:([\w.]+)|)/.exec(ua) ||
       /(Trident)[\/]([\w.]+)/.exec(ua) || [];

    return {
        browser: match[1] || "",
        version: match[2] || "0"
    };
};
// Don't clobber any existing jQuery.browser in case it's different
if (!jQuery.browser) {
    matched = jQuery.uaMatch(navigator.userAgent);
    browser = {};

    if (matched.browser) {
        browser[matched.browser] = true;
        browser.version = matched.version;
    }

    // Chrome is Webkit, but Webkit is also Safari.
    if (browser.chrome) {
        browser.webkit = true;
    } else if (browser.webkit) {
        browser.safari = true;
    }

    jQuery.browser = browser;
}

If using jQuery version <1.9 ($.browser was removed in jQuery 1.9) use the following code instead:

$('.myClass').on('click', function (event) {
    if ($.browser.msie) {
        alert($.browser.version);
    }
});

If you don't want to use the useragent, you could also just do this for checking if the browser is IE. The commented code actually runs in IE browsers and turns the "false" to "true".

var isIE = /*@cc_on!@*/false;
if(isIE){
	//The browser is IE.
}else{
	//The browser is NOT IE.
}	

I know this is an old question, but in case anyone comes across it again and has issues with detecting IE11, here is a working solution for all current versions of IE.

var isIE = false;
if (navigator.userAgent.indexOf('MSIE') !== -1 || navigator.appVersion.indexOf('Trident/') > 0) {
    isIE = true;   
}

i've used this

function notIE(){
	var ua = window.navigator.userAgent;
	if (ua.indexOf('Edge/') > 0 || 
		ua.indexOf('Trident/') > 0 || 
		ua.indexOf('MSIE ') > 0){
	   return false;
	}else{
		return true;				
	}
}

Necromancing.

In order to not depend on the user-agent string, just check for a few properties:

if (document.documentMode) 
{
    console.log('Hello Microsoft IE User!');
}

if (!document.documentMode && window.msWriteProfilerMark) {
    console.log('Hello Microsoft Edge User!');
}

if (document.documentMode || window.msWriteProfilerMark) 
{
    console.log('Hello Microsoft User!');
}

if (window.msWriteProfilerMark) 
{
    console.log('Hello Microsoft User in fewer characters!');
}

Also, this detects the new Chredge/Edgium (Anaheim):

function isEdg()
{ 

    for (var i = 0, u="Microsoft", l =u.length; i < navigator.plugins.length; i++)
    {
        if (navigator.plugins[i].name != null && navigator.plugins[i].name.substr(0, l) === u)
            return true;
    }

    return false;
}

And this detects chromium:

function isChromium()
{ 

    for (var i = 0, u="Chromium", l =u.length; i < navigator.plugins.length; i++)
    {
        if (navigator.plugins[i].name != null && navigator.plugins[i].name.substr(0, l) === u)
            return true;
    }

    return false;
}

And this Safari:

if(window.safari)
{
	console.log("Safari, yeah!");
}

@SpiderCode's solution does not work with IE 11. Here is the best solution that I used henceforth in my code where I need browser detection for particular feature.

IE11 no longer reports as MSIE, according to this list of changes, it's intentional to avoid mis-detection.

What you can do if you really want to know it's IE is to detect the Trident/ string in the user agent if navigator.appName returns Netscape, something like (the untested);

Thanks to this answer

function isIE()
{
  var rv = -1;
  if (navigator.appName == 'Microsoft Internet Explorer')
  {
    var ua = navigator.userAgent;
    var re  = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");
    if (re.exec(ua) != null)
      rv = parseFloat( RegExp.$1 );
  }
  else if (navigator.appName == 'Netscape')
  {
    var ua = navigator.userAgent;
    var re  = new RegExp("Trident/.*rv:([0-9]{1,}[\.0-9]{0,})");
    if (re.exec(ua) != null)
      rv = parseFloat( RegExp.$1 );
  }
  return rv == -1 ? false: true;
}

Many answers here, and I'd like to add my input. IE 11 was being such an ass concerning flexbox (see all its issues and inconsistencies here) that I really needed an easy way to check if a user is using any IE browser (up to and including 11) but excluding Edge, because Edge is actually pretty nice.

Based on the answers given here, I wrote a simple function returning a global boolean variable which you can then use down the line. It's very easy to check for IE.

var isIE;
(function() {
    var ua = window.navigator.userAgent,
        msie = ua.indexOf('MSIE '),
        trident = ua.indexOf('Trident/');

    isIE = (msie > -1 || trident > -1) ? true : false;
})();

if (isIE) {
    alert("I am an Internet Explorer!");
}

This way you only have to do the look up once, and you store the result in a variable, rather than having to fetch the result on each function call. (As far as I know you don't even have to wait for document ready to execute this code as the user-agent is not related to the DOM.)

Below I found elegant way of doing this while googling ---

/ detect IE
var IEversion = detectIE();

if (IEversion !== false) {
  document.getElementById('result').innerHTML = 'IE ' + IEversion;
} else {
  document.getElementById('result').innerHTML = 'NOT IE';
}

// add details to debug result
document.getElementById('details').innerHTML = window.navigator.userAgent;

/**
 * detect IE
 * returns version of IE or false, if browser is not Internet Explorer
 */
function detectIE() {
  var ua = window.navigator.userAgent;

  // Test values; Uncomment to check result …

  // IE 10
  // ua = 'Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; Trident/6.0)';
  
  // IE 11
  // ua = 'Mozilla/5.0 (Windows NT 6.3; Trident/7.0; rv:11.0) like Gecko';
  
  // IE 12 / Spartan
  // ua = 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.71 Safari/537.36 Edge/12.0';
  
  // Edge (IE 12+)
  // ua = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2486.0 Safari/537.36 Edge/13.10586';

  var msie = ua.indexOf('MSIE ');
  if (msie > 0) {
    // IE 10 or older => return version number
    return parseInt(ua.substring(msie + 5, ua.indexOf('.', msie)), 10);
  }

  var trident = ua.indexOf('Trident/');
  if (trident > 0) {
    // IE 11 => return version number
    var rv = ua.indexOf('rv:');
    return parseInt(ua.substring(rv + 3, ua.indexOf('.', rv)), 10);
  }

  var edge = ua.indexOf('Edge/');
  if (edge > 0) {
    // Edge (IE 12+) => return version number
    return parseInt(ua.substring(edge + 5, ua.indexOf('.', edge)), 10);
  }

  // other browser
  return false;
}

Update to SpiderCode's answer to fix issues where the string 'MSIE' returns -1 but it matches 'Trident'. It used to return NAN, but now returns 11 for that version of IE.

   function msieversion() {
       var ua = window.navigator.userAgent;
       var msie = ua.indexOf("MSIE ");
       if (msie > -1) {
           return ua.substring(msie + 5, ua.indexOf(".", msie));
       } else if (navigator.userAgent.match(/Trident.*rv\:11\./)) {
           return 11;
       } else {
           return false;
       }
    }

I landed on this page in 2020, and I see that till IE5 all userAgent string have Trident, I'm not sure if they have changed anything. So checking only for Trident in the userAgent worked for me.

var isIE = navigator.userAgent.indexOf('Trident') > -1;

This is another way to detect IE without trying to look at the User-Agent:

var usingIE="__IE_DEVTOOLBAR_CONSOLE_EVAL_ERROR" in document;
alert("You are"+(usingIE?"":"n't")+" using Internet Explorer.");

I happened to find this by accident when I was testing if my site worked on IE, and I went to the debugger and clicked the folder icon. It has my scripts, and also a Dynamic Scripts folder that I didn't have. I opened it and found lots of browsertools.library.js files. Inside them I found stuff like:

document.__IE_DEVTOOLBAR_CONSOLE_EVAL_RESULT = undefined;
document.__IE_DEVTOOLBAR_CONSOLE_EVAL_ERROR = false;
document.__IE_DEVTOOLBAR_CONSOLE_EVAL_ERRORCODE = undefined;
try{
document.__IE_DEVTOOLBAR_CONSOLE_EVAL_RESULT = eval("\r\n//# sourceURL=browsertools://browsertools.library.js");
}
catch( eObj ){
document.__IE_DEVTOOLBAR_CONSOLE_EVAL_ERRORCODE = eObj.number;
document.__IE_DEVTOOLBAR_CONSOLE_EVAL_RESULT = eObj.message || eObj.description || eObj.toString();
document.__IE_DEVTOOLBAR_CONSOLE_EVAL_ERROR = true;
}

So I used these to test if the user's browser was IE. Just note this only works if you want to know if they have IE, not exactly what version of IE they have.

You can dectect all Internet Explorer (Last Version Tested 12).

<script>
    var $userAgent = '';
    if(/MSIE/i['test'](navigator['userAgent'])==true||/rv/i['test'](navigator['userAgent'])==true||/Edge/i['test'](navigator['userAgent'])==true){
       $userAgent='ie';
    } else {
       $userAgent='other';
    }
    
    alert($userAgent);
</script>

See here https://jsfiddle.net/v7npeLwe/

function msieversion() {
var ua = window.navigator.userAgent;
console.log(ua);
var msie = ua.indexOf("MSIE ");

if (msie > -1 || navigator.userAgent.match(/Trident.*rv:11\./)) { 
	// If Internet Explorer, return version numbe
	// You can do what you want only in IE in here.
	var version_number=parseInt(ua.substring(msie + 5, ua.indexOf(".", msie)));
	if (isNaN(version_number)) {
		var rv_index=ua.indexOf("rv:");
		version_number=parseInt(ua.substring(rv_index+3,ua.indexOf(".",rv_index)));
	}
	console.log(version_number);
} else {       
	//other browser   
    console.log('otherbrowser');
}
}

You should see the result in console, please use chrome Inspect.

I've placed this code in the document ready function and it only triggers in internet explorer. Tested in Internet Explorer 11.

var ua = window.navigator.userAgent;
ms_ie = /MSIE|Trident/.test(ua);
if ( ms_ie ) {
    //Do internet explorer exclusive behaviour here
}

This only work below IE 11 version.

var ie_version = parseInt(window.navigator.userAgent.substring(window.navigator.userAgent.indexOf("MSIE ") + 5, window.navigator.userAgent.indexOf(".", window.navigator.userAgent.indexOf("MSIE "))));

console.log("version number",ie_version);

JavaScript function to detect the version of Internet Explorer or Edge

function ieVersion(uaString) {
  uaString = uaString || navigator.userAgent;
  var match = /\b(MSIE |Trident.*?rv:|Edge\/)(\d+)/.exec(uaString);
  if (match) return parseInt(match[2])
}

Try doing like this

if ($.browser.msie && $.browser.version == 8) {
    //my stuff

}

I think it will help you Here

function checkIsIE() {
    var isIE = false;
    if (navigator.userAgent.indexOf('MSIE') !== -1 || navigator.appVersion.indexOf('Trident/') > 0) {
        isIE = true;
    }
    if (isIE)  // If Internet Explorer, return version number
    {
        kendo.ui.Window.fn._keydown = function (originalFn) {
            var KEY_ESC = 27;
            return function (e) {
                if (e.which !== KEY_ESC) {
                    originalFn.call(this, e);
                }
            };
        }(kendo.ui.Window.fn._keydown);

        var windowBrowser = $("#windowBrowser").kendoWindow({
            modal: true,
            id: 'dialogBrowser',
            visible: false,
            width: "40%",
            title: "Thông báo",
            scrollable: false,
            resizable: false,
            deactivate: false,
            position: {
                top: 100,
                left: '30%'
            }
        }).data('kendoWindow');
        var html = '<br /><div style="width:100%;text-align:center"><p style="color:red;font-weight:bold">Please use the browser below to use the tool</p>';
        html += '<img src="/Scripts/IPTVClearFeePackage_Box/Images/firefox.png"/>';
        html += ' <img src="/Scripts/IPTVClearFeePackage_Box/Images/chrome.png" />';
        html += ' <img src="/Scripts/IPTVClearFeePackage_Box/Images/opera.png" />';
        html += '<hr /><form><input type="button" class="btn btn-danger" value="Đóng trình duyệt" onclick="window.close()"></form><div>';
        windowBrowser.content(html);
        windowBrowser.open();

        $("#windowBrowser").parent().find(".k-window-titlebar").remove();
    }
    else  // If another browser, return 0
    {
        return false;
    }
}

You can use $.browser to get name, vendor and version information.

See http://api.jquery.com/jQuery.browser/