Warning, /graphics/krita/3rdparty/ext_qt/0053-WinInk-Prevent-Leave-event-confusing-mouse-capture-s.patch is written in an unsupported language. File is not indexed.

 From 5c29a8f7d18edd5097acd585ac302e8c14114d56 Mon Sep 17 00:00:00 2001
 From: Alvin Wong <alvinhochun@gmail.com>
 Date: Wed, 6 Apr 2022 18:46:29 +0800
 Subject: [PATCH] WinInk: Prevent Leave event confusing mouse capture state
 
 When mouse events are synthesized from tablet strokes, the WM_LBUTTONUP
 event can arrive later than WM_POINTERLEAVE if the pen is lifted very
 quickly. Normally, the mouse capture does not get released until the
 mouse button is released, and no Leave event is generated before that.
 However, WM_POINTERLEAVE does not consider the mouse capture state
 before unconditionally generating a Leave event. This confuses the mouse
 andling and no Enter event is sent before the following mouse events,
 which causes parts of Qt to think the cursor isn't inside the window.
 
 The fix is to not generate the Leave event on WM_POINTERLEAVE if mouse
 capture is active. In addition, when it does send the Leave event,
 immediately handle it synchronously, before more mouse events arrive,
 so that the next Enter event can be generated correctly.
 
 Another issue discovered is that, sometimes the Enter event arrives
 later than the Tablet events for unknown reasons. The fix (workaround)
 is also to handle the Enter event synchronously.
 ---
  .../windows/qwindowspointerhandler.cpp        | 23 ++++++++++++++++---
  1 file changed, 20 insertions(+), 3 deletions(-)
 
 diff --git a/src/plugins/platforms/windows/qwindowspointerhandler.cpp b/src/plugins/platforms/windows/qwindowspointerhandler.cpp
 index 9e518a262f..2da76a59ec 100644
 --- a/src/plugins/platforms/windows/qwindowspointerhandler.cpp
 +++ b/src/plugins/platforms/windows/qwindowspointerhandler.cpp
 @@ -657,13 +657,25 @@ bool QWindowsPointerHandler::translatePenEvent(QWindow *window, HWND hwnd, QtWin
          // The local coordinates may fall outside the window.
          // Wait until the next update to send the enter event.
          m_needsEnterOnPointerUpdate = true;
 +        qCDebug(lcQpaEvents) << "WM_POINTERENTER received, m_windowUnderPointer:" << window;
          break;
      }
      case WM_POINTERLEAVE:
          if (m_windowUnderPointer && m_windowUnderPointer == m_currentWindow) {
 -            QWindowSystemInterface::handleLeaveEvent(m_windowUnderPointer);
 -            m_windowUnderPointer = nullptr;
 -            m_currentWindow = nullptr;
 +            QWindowsWindow *platformWindow = static_cast<QWindowsWindow *>(window->handle());
 +            const bool hasCapture = platformWindow->hasMouseCapture();
 +            if (!hasCapture) {
 +                qCDebug(lcQpaEvents) << "Leaving window " << m_windowUnderPointer << "(WM_POINTERLEAVE)";
 +                QWindowSystemInterface::handleLeaveEvent(m_windowUnderPointer);
 +                m_windowUnderPointer = nullptr;
 +                m_currentWindow = nullptr;
 +                // Flush to make sure the Leave event gets processed before
 +                // we we potentially get more mouse events, so that Qt can
 +                // correctly generate a new Enter event for them.
 +                QWindowSystemInterface::flushWindowSystemEvents();
 +            } else {
 +                qCDebug(lcQpaEvents) << "WM_POINTERLEAVE blocked from sending Leave event due to existing mouse capture";
 +            }
          }
          QWindowSystemInterface::handleTabletLeaveProximityEvent(device, type, sourceDevice);
          break;
 @@ -682,10 +694,15 @@ bool QWindowsPointerHandler::translatePenEvent(QWindow *window, HWND hwnd, QtWin
                  // make sure we subscribe to leave events for this window
                  trackLeave(hwnd);
  
 +                qCDebug(lcQpaEvents) << "Entering window " << window << "(WM_POINTERDOWN / WM_POINTERUP / WM_POINTERUPDATE)";
                  QWindowSystemInterface::handleEnterEvent(window, localPos, globalPos);
                  m_currentWindow = window;
                  if (QWindowsWindow *wumPlatformWindow = QWindowsWindow::windowsWindowOf(target))
                      wumPlatformWindow->applyCursor();
 +                // Make sure the Enter event is processed before sending tablet
 +                // events. Without this, sometimes the tablet events reaches
 +                // the widget before the Enter event For unknown reasons.
 +                QWindowSystemInterface::flushWindowSystemEvents();
              }
          }
          const Qt::KeyboardModifiers keyModifiers = QWindowsKeyMapper::queryKeyboardModifiers();
 -- 
 2.24.1.windows.2