With recent WhatsApp Version 2.2243.11.0 and DF setting "All taskbars show relevant windows", for some reason WhatsApp displayed in mulitple taskbars.

is this problem fixed or has a workaround? (whatsapp desktop app is visible on both taskbar)

Its very annoying if you buy it for this functionality and if stopped working the way its supposed to

I can confirm this bug, after updating to version 10.
Whatsapp is always displayed in the Windows Taskbar as well, even though the application is open in the area of one of the additional taskbars.

This issue seems to be caused by this bug that's been reported a while back.

Until Whatsapp changed to a UWP app it hasn't been that annoying, but hopefully this will give a bigger reason to fix the bug.

i installed and used old whatsapp version since few days and but its now not supported (calls are interrupted, messages delayed)

there should be a way or a workaround we can apply (through your suggestions)