Detect “Do Not Track” with JavaScript
Do Not Track is an excellent idea. The DNT website describes it best:
Do Not Track is a technology and policy proposal that enables users to opt out of tracking by websites they do not visit, including analytics services, advertising networks, and social platforms. At present few of these third parties offer a reliable tracking opt out, and tools for blocking them are neither user-friendly nor comprehensive. Much like the popular Do Not Call registry, Do Not Track provides users with a single, simple, persistent choice to opt out of third-party web tracking.
The preference is sent from the client to the server via a HTTP header but you can also get its value using JavaScript:
// "1" or "unspecified"
if(navigator.doNotTrack == 1) {
// Do (or don't do) stuff.
}
If you wanted to be extreme about honoring your user's preference, you could use that to lazyload (or not) advertising, analytics, or other utilities. Probably a bit extreme but it's there for you to use!
![6 Things You Didn’t Know About Firefox OS]()
Firefox OS is all over the tech news and for good reason: Mozilla's finally given web developers the platform that they need to create apps the way they've been creating them for years -- with CSS, HTML, and JavaScript. Firefox OS has been rapidly improving...
![Create a CSS Cube]()
CSS cubes really showcase what CSS has become over the years, evolving from simple color and dimension directives to a language capable of creating deep, creative visuals. Add animation and you've got something really neat. Unfortunately each CSS cube tutorial I've read is a bit...
![Use Elements as Background Images with -moz-element]()
We all know that each browser vendor takes the liberty of implementing their own CSS and JavaScript features, and I'm thankful for that. Mozilla and WebKit have come out with some interesting proprietary CSS properties, and since we all know that cementing standards...
![CSS @supports]()
Feature detection via JavaScript is a client side best practice and for all the right reasons, but unfortunately that same functionality hasn't been available within CSS. What we end up doing is repeating the same properties multiple times with each browser prefix. Yuck. Another thing we...
Is the resulting value always a string or an integer except when unspecified (then it is a string), and are the values you stated the same cross-browser (especially the unspecified value)?
I really like how medium handles DNT.