The problem with child closing in Docking Nodes

[ImpDi]

Version/Branch of Dear ImGui:

Version 1.92.5, Branch: Docking

Back-ends:

imgui_impl_dx9.cpp + imgui_impl_win32.cpp

Compiler, OS:

Windows 10 + MSVC 2022

Full config/build information:

Dear ImGui 1.92.5 (19250)
--------------------------------
sizeof(size_t): 4, sizeof(ImDrawIdx): 2, sizeof(ImDrawVert): 20
define: __cplusplus=199711
define: _WIN32
define: _MSC_VER=1944
define: _MSVC_LANG=201402
define: IMGUI_HAS_VIEWPORT
define: IMGUI_HAS_DOCK
IM_ASSERT: runs expression: OK. expand size: OK
--------------------------------
io.BackendPlatformName: imgui_impl_win32
io.BackendRendererName: imgui_impl_dx9
io.ConfigFlags: 0x00000483
 NavEnableKeyboard
 NavEnableGamepad
 DockingEnable
 ViewportsEnable
io.ConfigDpiScaleFonts
io.ConfigDpiScaleViewports
io.ConfigViewportsNoDecoration
io.ConfigViewportsNoDefaultParent
io.ConfigNavCaptureKeyboard
io.ConfigInputTextCursorBlink
io.ConfigWindowsResizeFromEdges
io.ConfigMemoryCompactTimer = 60.0
io.BackendFlags: 0x00003C1E
 HasMouseCursors
 HasSetMousePos
 PlatformHasViewports
 HasMouseHoveredViewport
 HasParentViewport
 RendererHasVtxOffset
 RendererHasTextures
 RendererHasViewports
--------------------------------
io.Fonts: 1 fonts, Flags: 0x00000000, TexSize: 512,128
io.Fonts->FontLoaderName: stb_truetype
io.DisplaySize: 1264.00,761.00
io.DisplayFramebufferScale: 1.00,1.00
--------------------------------
style.WindowPadding: 8.00,8.00
style.WindowBorderSize: 1.00
style.FramePadding: 4.00,3.00
style.FrameRounding: 0.00
style.FrameBorderSize: 0.00
style.ItemSpacing: 8.00,4.00
style.ItemInnerSpacing: 4.00,4.00

Details:

When all, except the last child of Docking Node is closed, the last of them It acts like it's still in the Docking Node (should it be there? I thought it should close it). Also, to "fix" the window, you have to move it, which causes lag.

I'm using code from example_win32_directx9, which is in the Docking branch.

Screenshots/Video:

Docking_Bug.mp4

Minimal, Complete and Verifiable Example code:

ImGui::Begin("First Window", &bShowFirstWindow);
ImGui::End();

ImGui::Begin("Second Window", &bShowSecondWindow);
ImGui::End();