what do you mean? Can you explain?

what do you mean? Can you explain?

The System Details list shows you use a 32-bit Firefox 40.0 version. Are you really using that very old version or is this a problem with the user agent ?

• Mozilla/5.0(X11;U;Linux i686;en-US;rv:40.0)Gecko/20100101 Firefox/40.0

Can't you update ?

• https://www.mozilla.org/en-US/firefox/86.0/system-requirements/

The current requirements for Whatsapp seem to be Windows 8 or higher or Mac OS X 10.10 or higher and Firefox 60 or higher, no mention of supporting Linux.