Why is autocorrect not working on downloaded apps?

[iMore Question]

Autocorrect is working on my Mac normal when I’m on iMessage or Documents/Notes but it’s not working on downloaded apps like Firefox, Viber and WhatsApp. Please help

 

[Just_Me_D]

I don’t know, but it works with non-Apple apps like Microsoft Outlook and Google Mail. Hopefully members who have the apps you mentioned installed in their devices will reply soon.