Question: Given the recent "[encouragement](http://techcrunch.com/2014/07/28/facebook-moving-messages/)" by Facebook to migrate to a separate messenger app, and as a followup to the {very informative!} [answer to the question on URL/URI schemes supported by the Facebook app](https://stackoverflow.com/a/5707825/3372061), I've been wondering whether information regarding the Facebook messenger app [custom protocol](https://stackoverflow.com/a/3471554/3372061) of **`fb-messenger://`** is available.

The functionality I was looking for was an ability to click a button that would open a FB-messenger chat windows with the user whose numeric Facebook ID is known. This also needed to work if the Facebook app ([katana](https://play.google.com/store/apps/details?id=com.facebook.katana)) is not installed on the device (i.e. only the messenger, [orca](https://play.google.com/store/apps/details?id=com.facebook.orca)).

I found an [example](https://stackoverflow.com/a/20320386/3372061) of the desired [deep linking](https://developer.android.com/training/app-indexing/deep-linking.html) (`fb-messenger://user-thread/{user-id}`), but that didn't seem to work. I realized that FB has a tendency of revising the URIs every once in a while, since these are generally not supposed to be available to the public (as far as I understand).

Answer: 
This simply share a link

```
<a href="fb-messenger://share?link=encodedLink"></a>

```
Using chrome intents for Android: The below code opens FB messenger if installed. Else redirects to fallback URL.

```
<a href="intent://user/<yourid>/#Intent;scheme=fb-messenger;package=com.facebook.orca;S.browser_fallback_url=http://yourfllbackweburl;end"> Open Messenger</a>

```