PaperMC/paper-server/patches/unapplied/net/minecraft/server/commands/PlaceCommand.java.patch

--- a/net/minecraft/server/commands/PlaceCommand.java
+++ b/net/minecraft/server/commands/PlaceCommand.java
@@ -132,6 +132,7 @@
         if (!structurestart.isValid()) {
             throw PlaceCommand.ERROR_STRUCTURE_FAILED.create();
         } else {
+            structurestart.generationEventCause = org.bukkit.event.world.AsyncStructureGenerateEvent.Cause.COMMAND; // CraftBukkit - set AsyncStructureGenerateEvent.Cause.COMMAND as generation cause
             BoundingBox structureboundingbox = structurestart.getBoundingBox();
             ChunkPos chunkcoordintpair = new ChunkPos(SectionPos.blockToSectionCoord(structureboundingbox.minX()), SectionPos.blockToSectionCoord(structureboundingbox.minZ()));
             ChunkPos chunkcoordintpair1 = new ChunkPos(SectionPos.blockToSectionCoord(structureboundingbox.maxX()), SectionPos.blockToSectionCoord(structureboundingbox.maxZ()));