Meta to Discontinue Cross-Platform Messaging Between Instagram and Facebook

The change, effective from mid-December 2023, comes amid speculation of compliance with the EU's Digital Markets Act.

Meta is discontinuing the cross-platform messaging feature between Instagram and Facebook, which was introduced in 2020.
Starting mid-December 2023, users will not be able to start new conversations or calls with Facebook accounts from Instagram, and existing chats will become read-only.
Facebook accounts will no longer be able to view the active status of Instagram users and vice versa.
No specific reason for the change has been provided by Meta, but speculation suggests it may be related to the European Union's Digital Markets Act (DMA), which requires large messaging apps to be interoperable with each other.
Meta's other product, WhatsApp, has already started preparations to comply with the DMA, introducing a 'Third-Party Chats' feature.