According to Mental Outlaw on YouTube, the vulnerability describes a phishing attack, which isn’t a real vulnerability; as any app or service is prone to such attacks.

[–] jet@hackertalks.com 1 points 2 weeks ago

From the HN comments

https://www.soc.mil/IdM/publications/docs/general/Id_Privacy_Full.pdf

[–] jet@hackertalks.com 1 points 2 weeks ago* (last edited 2 weeks ago)

I often look at the total number of devices in a conversation to ensure I'm talking directly to a phone and not a desktop

Click on a contact in a conversation and it tells you how many linked devices they have.