How to add Custom POS Button?

1. In your POS, Click the "Gear" Icon settings in the upper right
    
2. Click "Plugins" in the general
    
3. Type " Custom POS buttons" in the search bar or scroll down until you see it.  
    
4. Please tick the box to enable it and click "Configure plugin".
    

   5. Add custom buttons > enable it > save.