From time to time I am receiving following error message in log while switching from Content Browser to Output Log tab in Editor (program doesn’t crash):
LogOutputDevice:Warning: === Handled error: ===
Ensure condition failed: TabBeingDraggedPtr.IsValid() [File:D:\Build++UE4+Release-4.12+Compile\Sync\Engine\Source\Runtime\Slate\Private\Framework\Docking\SDockingTabWell.cpp] [Line: 374]
Stack:
UE4Editor-Core.dll!FWindowsPlatformStackWalk::StackWalkAndDump() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsplatformstackwalk.cpp:183]
UE4Editor-Core.dll!FDebug::EnsureFailed() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\misc\outputdevice.cpp:327]
UE4Editor-Core.dll!FDebug::OptionallyLogFormattedEnsureMessageReturningFalse() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\misc\outputdevice.cpp:451]
UE4Editor-Slate.dll!SDockingTabWell::OnDrop() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\docking\sdockingtabwell.cpp:374]
UE4Editor-Slate.dll!::operator()() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4630]
UE4Editor-Slate.dll!FEventRouter::Route >() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:215]
UE4Editor-Slate.dll!FSlateApplication::RoutePointerUpEvent() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4621]
UE4Editor-Slate.dll!FSlateApplication::ProcessMouseButtonUpEvent() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5041]
UE4Editor-Slate.dll!FSlateApplication::OnMouseUp() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5021]
UE4Editor-Core.dll!FWindowsApplication::ProcessDeferredMessage() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:1510]
UE4Editor-Core.dll!FWindowsApplication::DeferMessage() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:1850]
UE4Editor-Core.dll!FWindowsApplication::ProcessMessage() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:745]
UE4Editor-Core.dll!FWindowsApplication::AppWndProc() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:667]
USER32.dll
USER32.dll
UE4Editor-Core.dll!FWindowsPlatformMisc::PumpMessages() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\windows\windowsplatformmisc.cpp:903]
UE4Editor.exe!FEngineLoop::Tick() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\launchengineloop.cpp:2729]
UE4Editor.exe!GuardedMain() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\launch.cpp:148]
UE4Editor.exe!GuardedMainWrapper() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor.exe!WinMain() [d:\build++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:200]
UE4Editor.exe!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264]
KERNEL32.DLL
ntdll.dll
ntdll.dll