[thisislife2]

Is this a per-contact setting or a "universal" one?

[zeeZ]

It's a universal setting. You have to enable it per third-party app, though. You get to choose whether you want to see them listed with WhatsApp chats or in a separate folder

[progval]

It's universal, but you need to whitelist specific apps people can message you from. This is what it looks like: https://i.imgur.com/0gKY76z.png

[odo1242]

Account-wide. Though you can only turn it on in Europe.

[benj111]

When you say Europe you mean the EU? I'm not seeing an option in the UK. (Yay Brexit)

[riffraff]

Yeah it's the EU, this is a result of the DMA regulation. I suppose the British government could enact a similar regulation tho.

[dfajgljsldkjag]

Each whatsapp user needs to enable the setting once to allow chats with multiple number of third party users.