How to solve this

when i am trying to make a Facebook app then i show this type of error…
plz guys help me to resolve this issue…

normal app is like this:::::::::::::;;

but when i will click on messenger show me a error:::::::::

The webviewer is not a full browser and doesn’t know what to do with fb-messenger://. So open the link in a external browser.

Another tip. You start your topics frequently with something like “How to solve this”. Could you please use a topic title that tells about your problem.