Div having contentEditable and display:grid cannot be edited if it is empty.

Source/core/rendering/RenderGrid.cpp

 /*
  * Copyright (C) 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1132 matching lines @@
         // Keep track of children overflowing their grid area as we might need to paint them even if the grid-area is
         // not visible
         if (child->logicalHeight() > overrideContainingBlockContentLogicalHeight
             || child->logicalWidth() > overrideContainingBlockContentLogicalWidth)
             m_gridItemsOverflowingGridArea.append(child);
     }
 
     for (const auto& row : sizingData.rowTracks)
         setLogicalHeight(logicalHeight() + row.baseSize());
 
+    LayoutUnit height = logicalHeight() + borderAndPaddingLogicalHeight();
+    if (hasLineIfEmpty())
+        height = std::max(height, minimumLogicalHeightForEmptyLine());
+
     // Min / max logical height is handled by the call to updateLogicalHeight in layoutBlock.
-
-    setLogicalHeight(logicalHeight() + borderAndPaddingLogicalHeight());
+    setLogicalHeight(height);
 }
 
 void RenderGrid::layoutPositionedObjects(bool relayoutChildren, PositionedLayoutBehavior info)
 {
     TrackedRendererListHashSet* positionedDescendants = positionedObjects();
     if (!positionedDescendants)
         return;
 
     bool containerHasHorizontalWritingMode = isHorizontalWritingMode();
     for (auto* child : *positionedDescendants) {
@@ skipping 567 matching lines @@
     if (isOutOfFlowPositioned())
         return "RenderGrid (positioned)";
     if (isAnonymous())
         return "RenderGrid (generated)";
     if (isRelPositioned())
         return "RenderGrid (relative positioned)";
     return "RenderGrid";
 }
 
 } // namespace blink