5 files changed, 19 insertions, 14 deletions
diff --git a/indra/llwindow/llwindowcallbacks.cpp b/indra/llwindow/llwindowcallbacks.cpp
index 474953d3a4..7e90ade423 100644
--- a/indra/llwindow/llwindowcallbacks.cpp
+++ b/indra/llwindow/llwindowcallbacks.cpp
@@ -175,9 +175,9 @@ BOOL LLWindowCallbacks::handleDeviceChange(LLWindow *window)
 	return FALSE;
 }
 
-void LLWindowCallbacks::handleDPIChanged(LLWindow *window, F32 ui_scale_factor, S32 window_width, S32 window_height)
+BOOL LLWindowCallbacks::handleDPIChanged(LLWindow *window, F32 ui_scale_factor, S32 window_width, S32 window_height)
 {
-
+	return FALSE;
 }
 
 void LLWindowCallbacks::handlePingWatchdog(LLWindow *window, const char * msg)
diff --git a/indra/llwindow/llwindowcallbacks.h b/indra/llwindow/llwindowcallbacks.h
index de789a71d9..47d5a18858 100644
--- a/indra/llwindow/llwindowcallbacks.h
+++ b/indra/llwindow/llwindowcallbacks.h
@@ -65,7 +65,7 @@ public:
 	virtual void handleDataCopy(LLWindow *window, S32 data_type, void *data);
 	virtual BOOL handleTimerEvent(LLWindow *window);
 	virtual BOOL handleDeviceChange(LLWindow *window);
-	virtual void handleDPIChanged(LLWindow *window, F32 ui_scale_factor, S32 window_width, S32 window_height);
+	virtual BOOL handleDPIChanged(LLWindow *window, F32 ui_scale_factor, S32 window_width, S32 window_height);
 
 	enum DragNDropAction {
 		DNDA_START_TRACKING = 0,// Start tracking an incoming drag
diff --git a/indra/llwindow/llwindowwin32.cpp b/indra/llwindow/llwindowwin32.cpp
index 062f922006..321792eb14 100644
--- a/indra/llwindow/llwindowwin32.cpp
+++ b/indra/llwindow/llwindowwin32.cpp
@@ -2627,15 +2627,17 @@ LRESULT CALLBACK LLWindowWin32::mainWindowProc(HWND h_wnd, UINT u_msg, WPARAM w_
 				lprc_new_scale = (LPRECT)l_param;
 				S32 new_width = lprc_new_scale->right - lprc_new_scale->left;
 				S32 new_height = lprc_new_scale->bottom - lprc_new_scale->top;
-				window_imp->mCallbacks->handleDPIChanged(window_imp, new_scale, new_width, new_height);
-				SetWindowPos(h_wnd,
-					HWND_TOP,
-					lprc_new_scale->left,
-					lprc_new_scale->top,
-					new_width,
-					new_height,
-					SWP_NOZORDER | SWP_NOACTIVATE);
-					return 0;
+				if (window_imp->mCallbacks->handleDPIChanged(window_imp, new_scale, new_width, new_height))
+				{
+					SetWindowPos(h_wnd,
+						HWND_TOP,
+						lprc_new_scale->left,
+						lprc_new_scale->top,
+						new_width,
+						new_height,
+						SWP_NOZORDER | SWP_NOACTIVATE);
+				}
+				return 0;
 			}
 
 		case WM_SETFOCUS:
diff --git a/indra/newview/llviewerwindow.cpp b/indra/newview/llviewerwindow.cpp
index cce988c2fe..61505b7c07 100644
--- a/indra/newview/llviewerwindow.cpp
+++ b/indra/newview/llviewerwindow.cpp
@@ -1599,17 +1599,20 @@ BOOL LLViewerWindow::handleDeviceChange(LLWindow *window)
 	return FALSE;
 }
 
-void LLViewerWindow::handleDPIChanged(LLWindow *window, F32 ui_scale_factor, S32 window_width, S32 window_height)
+BOOL LLViewerWindow::handleDPIChanged(LLWindow *window, F32 ui_scale_factor, S32 window_width, S32 window_height)
 {
     if (ui_scale_factor >= MIN_UI_SCALE && ui_scale_factor <= MAX_UI_SCALE)
     {
+        gSavedSettings.setF32("LastSystemUIScaleFactor", ui_scale_factor);
         gSavedSettings.setF32("UIScaleFactor", ui_scale_factor);
         LLViewerWindow::reshape(window_width, window_height);
         mResDirty = true;
+        return TRUE;
     }
     else
     {
         LL_WARNS() << "DPI change caused UI scale to go out of bounds: " << ui_scale_factor << LL_ENDL;
+        return FALSE;
     }
 }
 
diff --git a/indra/newview/llviewerwindow.h b/indra/newview/llviewerwindow.h
index 72b7370621..a134dfaaa9 100644
--- a/indra/newview/llviewerwindow.h
+++ b/indra/newview/llviewerwindow.h
@@ -211,7 +211,7 @@ public:
 	/*virtual*/ void handleDataCopy(LLWindow *window, S32 data_type, void *data);
 	/*virtual*/ BOOL handleTimerEvent(LLWindow *window);
 	/*virtual*/ BOOL handleDeviceChange(LLWindow *window);
-	/*virtual*/ void handleDPIChanged(LLWindow *window, F32 ui_scale_factor, S32 window_width, S32 window_height);
+	/*virtual*/ BOOL handleDPIChanged(LLWindow *window, F32 ui_scale_factor, S32 window_width, S32 window_height);
 
 	/*virtual*/ void handlePingWatchdog(LLWindow *window, const char * msg);
 	/*virtual*/ void handlePauseWatchdog(LLWindow *window);