I have a contact signup system with a button to send whatsapp message to whatsappweb.
When I click this button, it opens a whatsappweb tab in the conversation with that contact:
<a href="https://wa.me/55'.$telefone.'" target="_blank">Mandar WhatsApp</a>
How to click, it opens this link in the tab where whatsappweb is already open? Because whatsappweb only allows 1 open tab, whenever I click on some conversation, I have to go close the other already opened tab of whatsapp.
You can use php, javascript, jquery.