qt: Improve comments in WalletController::getOrCreateWallet()

Author: hebasto

src/qt/walletcontroller.cpp

@@ -128,8 +128,14 @@ WalletModel* WalletController::getOrCreateWallet(std::unique_ptr<interfaces::Wal
     }
 
     // Instantiate model and register it.
-    WalletModel* wallet_model = new WalletModel(std::move(wallet), m_client_model, m_platform_style, nullptr);
-    // Handler callback runs in a different thread so fix wallet model thread affinity.
+    WalletModel* wallet_model = new WalletModel(std::move(wallet), m_client_model, m_platform_style,
+                                                nullptr /* required for the following moveToThread() call */);
+
+    // Move WalletModel object to the thread that created the WalletController
+    // object (GUI main thread), instead of the current thread, which could be
+    // an outside wallet thread or RPC thread sending a LoadWallet notification.
+    // This ensures queued signals sent to the WalletModel object will be
+    // handled on the GUI event loop.
     wallet_model->moveToThread(thread());
     // setParent(parent) must be called in the thread which created the parent object. More details in #18948.
     GUIUtil::ObjectInvoke(this, [wallet_model, this] {
@@ -161,7 +167,6 @@ WalletModel* WalletController::getOrCreateWallet(std::unique_ptr<interfaces::Wal
     // Re-emit coinsSent signal from wallet model.
     connect(wallet_model, &WalletModel::coinsSent, this, &WalletController::coinsSent);
 
-    // Notify walletAdded signal on the GUI thread.
     Q_EMIT walletAdded(wallet_model);
 
     return wallet_model;