I have installed WhatsApp (as WhatsDesk, a snap package) and Signal Desktop on my Linux machines.
Recently, my phone broke, and I won’t be using WhatsApp or Signal on a phone anytime soon. This happened about a week ago, and until now, WhatsApp and Signal have continued to work.
Will WhatsApp and / or Signal keep working on my desktop (as long as I don’t manually log out), and if not: how long until I get logged out?
I see this message on my Whatsapp Web app (in Linux using Firefox)
Send and receive messages without keeping your phone online. Use WhatsApp on up to 4 linked devices and 1 phone at the same time.
On that basis, I would suggest that there isn't a problem to concern yourself about whilst you are sourcing a replacement.
Whatsapp is activated/authorised by using a mobile number.
It doesnt matter if you never use the phone again. However you need to continue owning that number, so keep your SIM valid.
If you let it lapse and the number is assigned to someone else, and if they activate whatsapp on their phone, you will lose everything.
