Edge claims to support webkitSpeechRecognition, but it doesn't work (discussion here, doesn't work on websites meant for testing, like this mozilla one, with the error "Error occurred in recognition: language-not-supported" despite my US english UI).
How can I detect if webkitSpeechRecognition is actually supported? I tried to filter out Edge by looking at the user agent, but it shows up as Chrome, and I'd prefer to just use feature detection rather than looking at the user agent anyway. I'd like to check this without requesting microphone permission (if I did request microphone permission, I'd have to wait for them to accept, and then see the language-not-supported error). Is there a simple way to check this, similar to just checking the value of window["webkitSpeechRecognition"] (which is defined in Edge, despite not working)?
If you want to check the support for webkitSpeechRecognition then you can refer to the JS code example below.
if ('SpeechRecognition' in window || 'webkitSpeechRecognition' in window)
{
console.log("speech recognition API supported");
}
else
{
console.log("speech recognition API not supported")
}
Output in MS Edge 88.0.705.56:
However, if you directly try to make a test using webkitSpeechRecognition then it will not work.
It looks like this feature is currently under development and to use it we need to enable it by passing the command line arguments.
I suggest you refer to the steps below.
Create a shortcut of the Edge chromium-browser.
Right-click the shortcut file and go to Properties.
Under Shortcut tab, in the Target textbox, add --enable-features=msSpeechRecognition after the msedge.exe path. Make sure to add 1 space between the path and command-line argument.
It should look like below.
Click on the OK button to close the properties window.
Launch the Edge browser via shortcut and visit any sample code example for SpeechRecognition. Here I am making a test with this example.
Output in MS Edge 88.0.705.56:
In addition, it's useful to check for errors (as shown in the above example source code, see below, https://www.google.com/intl/en/chrome/demos/speech.html): for instance audio might be disabled if not on a https website.
recognition.onerror = function(event) {
if (event.error == 'no-speech') {
start_img.src = '/intl/en/chrome/assets/common/images/content/mic.gif';
showInfo('info_no_speech');
ignore_onend = true;
}
if (event.error == 'audio-capture') {
start_img.src = '/intl/en/chrome/assets/common/images/content/mic.gif';
showInfo('info_no_microphone');
ignore_onend = true;
}
if (event.error == 'not-allowed') {
if (event.timeStamp - start_timestamp < 100) {
showInfo('info_blocked');
} else {
showInfo('info_denied');
}
ignore_onend = true;
}
};
Is it possible to determine if Google Chrome is in incognito mode via a script?
Edit: I actually meant is it possible via user-script, but the answers assume JavaScript is running on a web page. I've re-asked the question here in regards to user scripts.
The functionality of this answer is Chrome version dependant. The most recent comment was this works in v90
Yes. The FileSystem API is disabled in incognito mode. Check out https://jsfiddle.net/w49x9f1a/ when you are and aren't in incognito mode.
Sample code:
var fs = window.RequestFileSystem || window.webkitRequestFileSystem;
if (!fs) {
console.log("check failed?");
} else {
fs(window.TEMPORARY,
100,
console.log.bind(console, "not in incognito mode"),
console.log.bind(console, "incognito mode"));
}
In Chrome 74 to 84.0.4147.135 you can determine this by estimating the available file system storage space
See the jsfiddle
if ('storage' in navigator && 'estimate' in navigator.storage) {
const {usage, quota} = await navigator.storage.estimate();
console.log(`Using ${usage} out of ${quota} bytes.`);
if(quota < 120000000){
console.log('Incognito')
} else {
console.log('Not Incognito')
}
} else {
console.log('Can not detect')
}
One way is to visit a unique URL and then check to see whether a link to that URL is treated as visited by CSS.
You can see an example of this in "Detecting Incognito" (Dead link).
Research paper by same author to replace Detecting Incognito link above
In main.html add an iframe,
<iframe id='testFrame' name='testFrame' onload='setUniqueSource(this)' src='' style="width:0; height:0; visibility:hidden;"></iframe>
, and some JavaScript code:
function checkResult() {
var a = frames[0].document.getElementById('test');
if (!a) return;
var color;
if (a.currentStyle) {
color = a.currentStyle.color;
} else {
color = frames[0].getComputedStyle(a, '').color;
}
var visited = (color == 'rgb(51, 102, 160)' || color == '#3366a0');
alert('mode is ' + (visited ? 'NOT Private' : 'Private'));
}
function setUniqueSource(frame) {
frame.src = "test.html?" + Math.random();
frame.onload = '';
}
Then in test.html that are loaded into the iFrame:
<style>
a:link { color: #336699; }
a:visited { color: #3366A0; }
</style>
<script>
setTimeout(function() {
var a = document.createElement('a');
a.href = location;
a.id = 'test';
document.body.appendChild(a);
parent.checkResult();
}, 100);
</script>
NOTE: trying this from the filesystem can make Chrome cry about "Unsafe Javascript". It
will, however, work serving from a webserver.
You can, in JavaScript, see JHurrah's answer. Except for not highlighting links, all incognito mode does is not save browse history and cookies. From google help page:
Webpages that you open and files downloaded while you are incognito
aren't recorded in your browsing and
download histories.
All new cookies are deleted after you close all incognito windows
that you've opened.
As you can see the differences between normal browsing and incognito happen after you visit the webpage, hence there is nothing that browser communicates to the server when it's in this mode.
You can see what exactly your browser sends to the server using one of many HTTP request analysers, like this one here. Compare the headers between normal session and incognito and you will see no difference.
If you are developing an Extension then you can use the tabs API to determine if a window/tab incognito.
More information can be found here.
If you are just working with a webpage, it is not easy, and it is designed to be that way. However, I have noticed that all attempts to open a database (window.database) fail when in incongnito, this is because when in incognito no trace of data is allowed to be left on the users machine.
I haven't tested it but I suspect all calls to localStorage fail too.
For those looking for a solution, here's a brief rundown of the current methods of detecting Private Browsing modes in various browsers as of October 2021:
Chromium: Similar to Vinnie James's answer, call navigator.storage.estimate(), grab the quota property and compare it to performance.memory.jsHeapSizeLimit. If the quota property is less than jsHeapSizeLimit, it's incognito. If jsHeapSizeLimit is undefined, use 1073741824 (1 GiB).
Safari for macOS: Use safari.pushNotification.requestPermission on a non-existent push server & grab the error. If "gesture" does not appear in the error, it's in private mode.
Safari for iOS: Create an iframe & add an error event listener using contentWindow.applicationCache on the iframe. If the error trips, it's in private mode.
Firefox: navigator.serviceWorker will be undefined in a private window.
Internet Explorer: window.indexedDB will be undefined in InPrivate mode.
You can see an implementation of these methods in the detectIncognito script I have available on GitHub.
Update This seems to not be working anymore
This uses a promise to wait for the asynchronous code to set a flag, so we can use it synchronously afterward.
let isIncognito = await new Promise((resolve, reject)=>{
var fs = window.RequestFileSystem || window.webkitRequestFileSystem;
if (!fs) reject('Check incognito failed');
else fs(window.TEMPORARY, 100, ()=>resolve(false), ()=>resolve(true));
});
then we can do
if(isIncognito) alert('in incognito');
else alert('not in incognito');
Note, to use await you need to be inside an async function. If you're not, you can wrap all your code inside one to be able to
Quick function based on Alok's Answer (note: this is asynchronous)
Update - not working anymore
function ifIncognito(incog,func){
var fs = window.RequestFileSystem || window.webkitRequestFileSystem;
if (!fs) console.log("checking incognito failed");
else {
if(incog) fs(window.TEMPORARY, 100, ()=>{}, func);
else fs(window.TEMPORARY, 100, func, ()=>{});
}
}
usage:
ifIncognito(true, ()=>{ alert('in incognito') });
// or
ifIncognito(false, ()=>{ alert('not in incognito') });
Here is the suggested answer written in ES6 syntaxt and slightly cleand up.
const isIncognito = () => new Promise((resolve, reject) => {
const fs = window.RequestFileSystem || window.webkitRequestFileSystem;
if (!fs) {
reject('Cant determine whether browser is running in incognito mode!');
}
fs(window.TEMPORARY, 100, resolve.bind(null, false), resolve.bind(null, true));
});
// Usage
isIncognito()
.then(console.log)
.catch(console.error)
Other answers seem to be no longer valid in recent chrome versions.
The idea is to find out storage estimates to determine if the tab is incognito or not. Storage size is less for incognito tabs.
Run this code in both normal and incognito window and note down the quota size.
const {quota} = await navigator.storage.estimate();
console.log(quota);
use quota size difference to implement the logic for incognito mode detection.
below logic works for Chrome v105:
const { quota } = await navigator.storage.estimate();
if (quota.toString().length === 10) {
console.log("gotcha: this is incognito tab"); //quota = 1102885027
} else {
console.log("this is a normal tab"); //quota = 296630877388
}
Also, look at this solution for much wider support (includes other browsers as well)
detectIncognito.ts
demo: https://detectincognito.com/
This works in May 2021: https://jsfiddle.net/2b1dk8oa/
The script has to be executed in a webpage, which is in an iframe.
try{
var ls = localStorage;
alert("You are not in Incognito Mode.");
}
catch(e) { alert("You are in Incognito Mode."); }
im building an app through phonegap, with a geolocation button.
if a user denies permission for geolocation the first time, how can i ask for permission again when they click the geolocation button again?
my code structure at the moment is:
function getLocation() {
if(navigator.geolocation) {
navigator.geolocation.getCurrentPosition(showPosition, positionError);
} else {
hideLoadingDiv()
showError('Geolocation is not supported by this device')
}
}
function positionError() {
hideLoadingDiv()
showError('Geolocation is not enabled. Please enable to use this feature')
}
You can't.
The only thing you can do is to display the instructions to reactivate the location sharing in his browser's settings (https://support.google.com/chrome/answer/142065?hl=en).
Two ways of doing this:
If you have a version of Chrome bigger than 83.0.4103.97 then use the lock icon in the URL
For older versions of Chrome the bellow code will work fine:
The bellow code only works on Chrome.
Steps:
Open Chrome
Open the console
Copy in the console
var allowGeoRecall = true;
var countLocationAttempts = 0;
Copy in the console the functions
function getLocation() {
console.log('getLocation was called')
if(navigator.geolocation) {
navigator.geolocation.getCurrentPosition(showPosition,
positionError);
} else {
hideLoadingDiv()
console.log('Geolocation is not supported by this device')
}
}
function positionError() {
console.log('Geolocation is not enabled. Please enable to use this feature')
if(allowGeoRecall && countLocationAttempts < 5) {
countLocationAttempts += 1;
getLocation();
}
}
function showPosition(){
console.log('posititon accepted')
allowGeoRecall = false;
}
Run the function in the console
getLocation();
After running this you will be asked to allow to share your position. If your response is negative you will be asked again until you agree.
HINT: If your user has a negative response, let him know why you need the coordinates. Is vital for him to understand that this step is vital for the good run of the web app.
This can be reset in Page Info which can be accessed by clicking the lock icon next to the URL and allowing Location
I'm working with the HTML5 geolocation api. I'm getting a weird error. i got a function called doGeolocate that is called when the user land on the page. That load the map with the wright location data. And i got a button that recall the same function when ever the user want to recenter the map. But when a user tap the button on a desktop(chrome,opera, safari) except firefox it doesn't work.
While on the other there is no problem. Once debug it seem like the code locationCallback isn't call properly the second time even tho it is on load.
doGeolocate: function(){
if (navigator.geolocation) {
console.log("doGeolocate");
var locationCallback = helper.callback(this, function(position) {
this.initialGeolocationPosition(position);
if(!this.positionMarker){
this.createPositionMarker(position);
}
});
var err = function(err) {
console.log("");
};
var options = {
maximumAge: 0
};
navigator.geolocation.getCurrentPosition(locationCallback,err,options);
}
},
function goHome() {
if (window.home) { // NS
window.home();
}
else { // IE and Google Chrome
if (navigator.appVersion.split("MSIE")[1] <= 7) { // IE 4-7
window.location = "about:home";
}
else if (window.location.href) { // Google Chrome
window.location.href = "??????????"; // <<-- what is the built-in
} // link for the home button
else { // IE 8, 9
// ...
}
}
}
However, I do not know the built-in link for the home button in Google Chrome. Does anybody has an idea?
PS. The JavaScript code is incomplete and just a snippet!
In Chrome, the home page is either an actual URL, or the New Tab page.
So, it would be chrome://newtab/, except that if you try this on a page, you'll raise this security error:
Not allowed to load local resource:
chrome://newtab/
(see the error in Chrome's Developer Tools)
So, I don't think it's possible. I could be wrong, I'm no expert on Chrome.
chrome://newtab/ does take you to the right place if you paste it into your address bar, but that is obviously useless to you.