How to know if your WhatsApp messages are being secretly read by others?
On WhatsApp web, the primary device needs an internet connection but in multi device support facility, there is no need for an internet connection in the primary device. These are the features with which you can use WhatsApp on more than one device. Someone can also read your messages with the WhatsApp web or multi-device support facility.
Here is how to check whether your messages are read by others or not.