From d6fa4d4f98f15f6b21ebffcff0bfa3a2f6b8a76a Mon Sep 17 00:00:00 2001
From: Alexander Babikov <lemondrops358@gmail.com>
Date: Thu, 6 Mar 2025 22:20:13 +0500
Subject: [PATCH] Disable Win11 rounded corners on the secondary monitor
 windows

---
 src/qt/qt_mainwindow.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/qt/qt_mainwindow.cpp b/src/qt/qt_mainwindow.cpp
index 9802a2666..036f56375 100644
--- a/src/qt/qt_mainwindow.cpp
+++ b/src/qt/qt_mainwindow.cpp
@@ -816,6 +816,10 @@ MainWindow::initRendererMonitorSlot(int monitor_index)
         if (vid_resize == 2)
             secondaryRenderer->setFixedSize(fixed_size_x, fixed_size_y);
         secondaryRenderer->setWindowIcon(this->windowIcon());
+#ifdef Q_OS_WINDOWS
+        auto cornerPreference = DWMWCP_DONOTROUND;
+        DwmSetWindowAttribute((HWND) secondaryRenderer->winId(), DWMWA_WINDOW_CORNER_PREFERENCE, (LPCVOID) &cornerPreference, sizeof(cornerPreference));
+#endif
         if (show_second_monitors) {
             secondaryRenderer->show();
             if (window_remember) {