File mozilla-bmo1998188.patch of Package thunderbird146

diff --git a/xpfe/appshell/AppWindow.cpp b/xpfe/appshell/AppWindow.cpp
index eba6c33224..9b5e7b5d3a 100644
--- a/xpfe/appshell/AppWindow.cpp
+++ b/xpfe/appshell/AppWindow.cpp
@@ -751,8 +751,8 @@ nsresult AppWindow::MoveResize(const Maybe<DesktopPoint>& aPosition,
   return NS_OK;
 }
 
-NS_IMETHODIMP AppWindow::Center(nsIAppWindow* aRelative, bool aScreen,
-                                bool aAlert) {
+nsresult AppWindow::CenterImpl(nsIAppWindow* aRelative, bool aScreen,
+                               bool aAlert, bool aAllowCenteringForSizeChange) {
   DesktopIntRect rect;
   bool screenCoordinates = false, windowCoordinates = false;
   nsresult result;
@@ -820,12 +820,20 @@ NS_IMETHODIMP AppWindow::Center(nsIAppWindow* aRelative, bool aScreen,
   SetPositionDesktopPix(newPos.x, newPos.y);
 
   // If moving the window caused it to change size, re-do the centering.
-  if (GetSize() != ourDevSize) {
-    return Center(aRelative, aScreen, aAlert);
+  // Allow only one recursion here.
+  if (GetSize() != ourDevSize && aAllowCenteringForSizeChange) {
+    return CenterImpl(aRelative, aScreen, aAlert,
+                      /* aAllowCenteringForSizeChange */ false);
   }
   return NS_OK;
 }
 
+NS_IMETHODIMP AppWindow::Center(nsIAppWindow* aRelative, bool aScreen,
+                                bool aAlert) {
+  return CenterImpl(aRelative, aScreen, aAlert,
+                    /* aAllowCenteringForSizeChange */ true);
+}
+
 NS_IMETHODIMP AppWindow::Repaint(bool aForce) {
   // XXX First Check In
   NS_ASSERTION(false, "Not Yet Implemented");
diff --git a/xpfe/appshell/AppWindow.h b/xpfe/appshell/AppWindow.h
index 6ffce77706..b29697fba4 100644
--- a/xpfe/appshell/AppWindow.h
+++ b/xpfe/appshell/AppWindow.h
@@ -374,6 +374,8 @@ class AppWindow final : public nsIBaseWindow,
                       const Maybe<LayoutDeviceIntSize>& aSize, bool aRepaint);
   nsresult MoveResize(const Maybe<DesktopPoint>& aPosition,
                       const Maybe<DesktopSize>& aSize, bool aRepaint);
+  nsresult CenterImpl(nsIAppWindow* aRelative, bool aScreen, bool aAlert,
+                      bool aAllowCenteringForSizeChange);
   nsCOMPtr<nsIXULStore> mLocalStore;
   bool mIsWidgetInFullscreen = false;
 };