diff --git a/src/AcDream.App/Rendering/GameWindow.cs b/src/AcDream.App/Rendering/GameWindow.cs
index c910eabd..67137574 100644
--- a/src/AcDream.App/Rendering/GameWindow.cs
+++ b/src/AcDream.App/Rendering/GameWindow.cs
@@ -7093,6 +7093,15 @@ public sealed class GameWindow : IDisposable
             System.Math.Clamp(fogColor.Z, 0f, 1f),
             1f);
 
+        // §4 outdoor full-world flap (2026-06-10): the depth clear DEPENDS on the depth
+        // write mask — glClear(GL_DEPTH_BUFFER_BIT) is silently gated by glDepthMask.
+        // A pass that leaked DepthMask(false) at frame end (EnvCellRenderer's empty
+        // Transparent pass, fixed same-day) turned this clear into a no-op and the whole
+        // world failed GL_LESS against its own previous-frame depth ghost. Per
+        // feedback_render_self_contained_gl_state: the clear site asserts the state it
+        // depends on rather than inheriting it. The [gl-state] tripwire still detects
+        // any future leak.
+        _gl.DepthMask(true);
         _gl!.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit | ClearBufferMask.StencilBufferBit);
 
         // WB GameScene.cs:830-843 establishes CW as the frame-global
diff --git a/src/AcDream.App/Rendering/Wb/EnvCellRenderer.cs b/src/AcDream.App/Rendering/Wb/EnvCellRenderer.cs
index 064cb264..2fe1a37a 100644
--- a/src/AcDream.App/Rendering/Wb/EnvCellRenderer.cs
+++ b/src/AcDream.App/Rendering/Wb/EnvCellRenderer.cs
@@ -1016,31 +1016,17 @@ public sealed unsafe class EnvCellRenderer : IDisposable
         int passIdx = (int)renderPass;
         if (passIdx < 0 || passIdx > 2) return;
 
+        // §4 outdoor full-world flap (2026-06-10): hoisted from below the SSBO uploads.
+        // Without the global VAO nothing can draw, and returning AFTER the pass state
+        // was established leaked it (same early-out shape as the totalDraws==0 leak —
+        // see the comment on the state-establish block below).
+        var globalVao = _meshManager.GlobalBuffer?.VAO ?? 0u;
+        if (globalVao == 0) return;
+
         // WB BaseObjectRenderManager.cs:715-716:
         shader.Use();
         shader.SetInt("uFilterByCell", 0);
 
-        // Phase U.4 ROOT-CAUSE FIX (cell-shell "transparent walls / only bluish
-        // background, flickering when moving"): establish this pass's BLEND + DepthMask
-        // state OURSELVES rather than inheriting it. Render(Opaque) runs right after the
-        // terrain draw (which sets neither) and after particles / last frame's transparent
-        // pass — so whatever left GL_BLEND enabled made the OPAQUE shells composite their
-        // (often sub-1.0 alpha) wall textures against the bluish clear color (terrain is
-        // Skip'd indoors), toggling with per-frame ordering → flicker. Mirror the working
-        // WbDrawDispatcher passes (Disable(Blend)+DepthMask(true) opaque;
-        // Enable(Blend)+DepthMask(false) transparent). Restored to opaque defaults at the
-        // end of the draw loop so a Transparent pass can't leak into later draws.
-        if (renderPass == WbRenderPass.Transparent)
-        {
-            _gl.Enable(EnableCap.Blend);
-            _gl.DepthMask(false);
-        }
-        else
-        {
-            _gl.Disable(EnableCap.Blend);
-            _gl.DepthMask(true);
-        }
-
         // WB BaseObjectRenderManager.cs:718-740: group batches by CullMode + additive flag.
         var batchesByCullMode = new Dictionary<int, List<(ObjectRenderBatch batch, int instanceCount, int instanceOffset)>>();
         int totalDraws = 0;
@@ -1078,6 +1064,35 @@ public sealed unsafe class EnvCellRenderer : IDisposable
         // WB BaseObjectRenderManager.cs:743:
         if (totalDraws == 0) return;
 
+        // Phase U.4 ROOT-CAUSE FIX (cell-shell "transparent walls / only bluish
+        // background, flickering when moving"): establish this pass's BLEND + DepthMask
+        // state OURSELVES rather than inheriting it. Mirror the working WbDrawDispatcher
+        // passes (Disable(Blend)+DepthMask(true) opaque; Enable(Blend)+DepthMask(false)
+        // transparent). Restored to opaque defaults at the end of the draw loop so a
+        // Transparent pass can't leak into later draws.
+        //
+        // §4 outdoor full-world flap fix (2026-06-10): this block MOVED below the
+        // totalDraws==0 early-out above. It used to run before the batch grouping, so a
+        // Transparent pass over a cell whose batches are ALL opaque (a plain cottage
+        // interior) set Blend-on/DepthMask-off and then returned at the count check
+        // WITHOUT reaching the restore. The frame ended with dmask=0; the NEXT frame's
+        // glClear(DEPTH) silently no-oped (depth clears honor glDepthMask), every world
+        // fragment failed GL_LESS against its own previous-frame depth ghost, and the
+        // whole screen dropped to the fog-tinted clear color — onset-locked to the
+        // building-flood merge (the first frame a flooded building shell draws), holding
+        // until camera rotation dropped the cell from the flood. From here down every
+        // path reaches the end-of-pass restore.
+        if (renderPass == WbRenderPass.Transparent)
+        {
+            _gl.Enable(EnableCap.Blend);
+            _gl.DepthMask(false);
+        }
+        else
+        {
+            _gl.Disable(EnableCap.Blend);
+            _gl.DepthMask(true);
+        }
+
         // WB BaseObjectRenderManager.cs:745-759: resize buffers if needed.
         if (totalDraws > _mdiCommandCapacity)
         {
@@ -1199,8 +1214,8 @@ public sealed unsafe class EnvCellRenderer : IDisposable
         }
 
         // WB BaseObjectRenderManager.cs:807-818: bind VAO + SSBOs + barrier.
-        var globalVao = _meshManager.GlobalBuffer?.VAO ?? 0u;
-        if (globalVao == 0) return;
+        // (globalVao validated at the top of the method — a return here would leak the
+        // pass state established above.)
         if (_currentVao != globalVao)
         {
             _gl.BindVertexArray(globalVao);