There is a simple step to hide the word "writing" when writing a message in WhatsApp.
If you have an Android smartphone, you can use the easy-to-use Flychat application to prevent your contacts from knowing you're online or "typing".
Flychat does not need as many permissions but only the screen overlay, it will show us a floating WhatsApp window (similar to Facebook Messenger) and therefore will be able to respond without opening the application.
The detail of this application is that it does not allow the user to receive or send pictures or voice notes and, if you receive them, open WhatsApp directly.
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