From 90caadef1f769d30debee971d490c2d6c84c074f Mon Sep 17 00:00:00 2001
From: zubiden <19638254+zubiden@users.noreply.github.com>
Date: Fri, 4 Jul 2025 14:12:19 +0200
Subject: [PATCH] GramJS: Fix API layer announcement (#6036)

---
 src/lib/gramjs/client/TelegramClient.ts | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/lib/gramjs/client/TelegramClient.ts b/src/lib/gramjs/client/TelegramClient.ts
index 36334d979..1d47536b2 100644
--- a/src/lib/gramjs/client/TelegramClient.ts
+++ b/src/lib/gramjs/client/TelegramClient.ts
@@ -335,6 +335,7 @@ class TelegramClient {
     }
 
     this.session.setAuthKey(this._sender.authKey);
+    // `_initWith` is used to announce our API layer to the server
     await this._sender.send(this._initWith(
       new Api.help.GetConfig(),
     ));
@@ -686,7 +687,11 @@ class TelegramClient {
   ): Promise<MTProtoSender> {
     const i = index || 0;
 
-    if (!this._exportedSenderPromises[dcId]) this._exportedSenderPromises[dcId] = {};
+    let shouldAnnounceLayer = false;
+    if (!this._exportedSenderPromises[dcId]) {
+      this._exportedSenderPromises[dcId] = {};
+      shouldAnnounceLayer = true;
+    }
     if (!this._exportedSenderRefCounter[dcId]) this._exportedSenderRefCounter[dcId] = {};
 
     if (!this._exportedSenderPromises[dcId][i] || shouldReconnect) {
@@ -730,6 +735,11 @@ class TelegramClient {
       this._exportedSenderReleaseTimeouts[dcId][i] = undefined;
     }
 
+    if (shouldAnnounceLayer) {
+      // Dummy request to let DC know about our API layer
+      sender.send(this._initWith(new Api.help.GetConfig()));
+    }
+
     return sender;
   }