This is a longstanding crash that has occurred since at least 4.13.
User Descriptions
Source Context
1205 void FSlateApplication::DrawWindowAndChildren( const TSharedRef<SWindow>& WindowToDraw, FDrawWindowArgs& DrawWindowArgs )
1206 {
1207 // On Mac, where child windows can be on screen even if their parent is hidden or minimized, we want to always draw child windows.
1208 // On other platforms we set bDrawChildWindows to true only if we draw the current window.
1209 bool bDrawChildWindows = PLATFORM_MAC;
1210
1211 // Only draw visible windows
1212 ***** if( WindowToDraw->IsVisible() && (!WindowToDraw->IsWindowMinimized() || FApp::UseVRFocus()) )
1213 {
1214 SLATE_CYCLE_COUNTER_SCOPE_CUSTOM(GSlateDrawWindowAndChildren, WindowToDraw->GetCreatedInLocation());
repro steps currently unknown
UE4Editor_Slate!FSlateApplication::DrawWindowAndChildren() [slateapplication.cpp:1213] UE4Editor_Slate!FSlateApplication::DrawWindowAndChildren() [slateapplication.cpp:1322] UE4Editor_Slate!FSlateApplication::DrawWindowAndChildren() [slateapplication.cpp:1322] UE4Editor_Slate!FSlateApplication::DrawWindowAndChildren() [slateapplication.cpp:1322] UE4Editor_Slate!FSlateApplication::PrivateDrawWindows() [slateapplication.cpp:1473] UE4Editor_Slate!FSlateApplication::DrawWindows() [slateapplication.cpp:1190] UE4Editor_Slate!FSlateApplication::TickApplication() [slateapplication.cpp:1777] UE4Editor_Slate!FSlateApplication::Tick() [slateapplication.cpp:1595] UE4Editor!FEngineLoop::Tick() [launchengineloop.cpp:3378] UE4Editor!GuardedMain() [launch.cpp:166] UE4Editor!GuardedMainWrapper() [launchwindows.cpp:134] UE4Editor!WinMain() [launchwindows.cpp:210] UE4Editor!__scrt_common_main_seh() [exe_common.inl:253] kernel32!BaseThreadInitThunk() ntdll!RtlUserThreadStart()
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