This issue can be solved by following simple commands. All you need is editor and sudo permission(usually your same password as user).
Open the file /etc/gdm3/custom.conf is this does not exist in your machine open /etc/gdm3/daemon.conf.
Then uncomment the line WaylandEnable=false that is remove the # at the start of the line, save it and then do a reboot.
Before starting this, you need to open web.whatsapp.com in your computer and sync your account with your mobile. Then go to the following website.
https://coolsymbol.com/zero-width-space-joiner-non-joiner-ltr-rtl-lrm-rlm-characters-symbols.html
Here click on either zero width joiner or zero width non joiner. Choose copy and paste in the web.whatsapp.com under any chat to whom you wish to send the empty message. In ubuntu or linux we can type this character by holding Ctrl+Shift+U and press 200C
Here is how it looks.
