Open WA.ME or new chat with WhatsApp Dual 
  
    WhatsApp  allows you to start a new chat with an unknown number simply by using the  wa.me URL from a browser  . However, this URL  only works with the main WhatsApp app  . If you have  a second WhatsApp account  through the  WhatsApp Dual  or Dual Messenger function that some devices such as Samsung Galaxy incorporate from the factory, it is necessary to apply the trick explained below to  force  the new chat with that stranger  to open in your account WhatsApp secondary  .. 
   
    In case you don't know, to open a new chat with a new number  without having to add it to the phonebook  , you just have to put  wa.me/codigopaisnumerotelefono  in the address bar of Chrome or the browser you use. This URL will give you the option to open the link with WhatsApp and will take you  directly to the chat window  with that number in the application. But as I said, this will only open the link with the main WhatsApp app. 
  Open WA.ME or new chat with WhatsApp Dual 
  The trick then is to send this link wa.me/codigopaisnumerotelefono  in a chat within the secondary application  or WhatsApp Dual. Clicking on the link will inevitably open it in that app and not the main app, which is the problem when using wa.me from the browser.. 
   
   The link can  be a sent message or a received message  , either doesn't matter.  The important thing is to have the blue, clickable  link within the secondary WhatsApp app . You do not need to send this link to someone else or ask them to send it to you in order to click it. You can start a chat with yourself in the application,  creating a status on your secondary WhatsApp  and in the text write the link  wa.me/tucodigopaistunumero  . By clicking on this link, you will open the  chat with your own phone number  to write links to chats with unknown numbers there. 
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