💬 Talking About Latest Broken #Layer213
In the latest Telegram Android update, something rather disruptive happened for MTProto clients. The developer introduced a new constructor for the type Channel, but on Layer 213 this constructor hasn’t actually been enabled in the schema.

🔎 What does this mean?
Essentially, deserialization of updates is now broken for all clients relying on the official TgScheme schema. Only Telegram Android continues to work correctly, since it uses its own backwards compatibility layer, allowing support for the old constructor (supported up to Layer 212) while simultaneously handling the new one.

Until the new constructor is officially adopted in the schema, one temporary solution is to manually re-add the old constructor for Channel into your local copy of the schema, ensuring compatibility with incoming updates.

🟡 UPD. 29 / 08 / 2025 - 23:00 UTC
The issue is still present in Layer 214. Despite the version bump, the new Channel constructor hasn’t been enabled in the official schema, so deserialization problems remain exactly the same as in Layer 213.

🟡 UPD. 30 / 08 / 2025 - 17:00 UTC
One of the Telegram developers confirmed that the issue was simply caused by an oversight. A fix is already planned and should be shipped in next week’s update.

✅ UPD. 31 / 08 / 2025 - 20:00 UTC
The issue has now been fixed by reverting the changes made to the Channel constructor.