diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 27a22fa8f..b62b14d67 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -73,7 +73,7 @@ nullAway = "0.9.9"
 spotless = "6.23.3"
 taskTree = "2.1.1"
 teavm = "0.10.0-SQUID.3"
-vanillaExtract = "0.1.1"
+vanillaExtract = "0.1.2"
 versionCatalogUpdate = "0.8.1"
 
 [libraries]
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlock.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlock.java
index 2bd6f00f4..a5f6eb34d 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlock.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlock.java
@@ -23,6 +23,7 @@
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.BlockGetter;
 import net.minecraft.world.level.Level;
+import net.minecraft.world.level.LevelAccessor;
 import net.minecraft.world.level.LevelReader;
 import net.minecraft.world.level.block.Block;
 import net.minecraft.world.level.block.EntityBlock;
@@ -174,6 +175,15 @@ public final void onNeighborChange(BlockState state, LevelReader world, BlockPos
         if (be instanceof AbstractComputerBlockEntity computer) computer.neighborChanged(neighbour);
     }
 
+    @Override
+    @Deprecated
+    public BlockState updateShape(BlockState state, Direction direction, BlockState neighborState, LevelAccessor level, BlockPos pos, BlockPos neighborPos) {
+        var be = level.getBlockEntity(pos);
+        if (be instanceof AbstractComputerBlockEntity computer) computer.neighbourShapeChanged(direction);
+
+        return super.updateShape(state, direction, neighborState, level, pos, neighborPos);
+    }
+
     @Nullable
     @Override
     @Deprecated
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlockEntity.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlockEntity.java
index 0ad1dc230..462945cbe 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlockEntity.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlockEntity.java
@@ -298,6 +298,17 @@ public void neighborChanged(BlockPos neighbour) {
         invalidSides = DirectionUtil.ALL_SIDES; // Mark all peripherals as dirty.
     }
 
+    /**
+     * Called when a neighbour block's shape changes.
+     * <p>
+     * Unlike {@link #neighborChanged(BlockPos)}, we don't update redstone, only peripherals.
+     *
+     * @param direction The side that changed.
+     */
+    public void neighbourShapeChanged(Direction direction) {
+        invalidSides |= 1 << direction.ordinal();
+    }
+
     /**
      * Update outputs in a specific direction.
      *
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableBlock.java b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableBlock.java
index cb5170444..bb9a728dc 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableBlock.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableBlock.java
@@ -196,6 +196,11 @@ public BlockState updateShape(BlockState state, Direction side, BlockState other
             if (level.getBlockEntity(pos) instanceof CableBlockEntity cable) cable.scheduleConnectionsChanged();
         }
 
+        var modem = state.getValue(MODEM);
+        if (modem.getFacing() == side && modem.isPeripheralOn() && level.getBlockEntity(pos) instanceof CableBlockEntity cable) {
+            cable.queueRefreshPeripheral();
+        }
+
         return level instanceof Level actualLevel
             ? state.setValue(CONNECTIONS.get(side), doesConnectVisually(state, actualLevel, pos, side))
             : state;
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableBlockEntity.java b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableBlockEntity.java
index 9ea7c4668..ea67bbf29 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableBlockEntity.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableBlockEntity.java
@@ -112,7 +112,7 @@ void neighborChanged(BlockPos neighbour) {
         }
     }
 
-    private void queueRefreshPeripheral() {
+    void queueRefreshPeripheral() {
         refreshPeripheral = true;
         TickScheduler.schedule(tickToken);
     }
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemFullBlock.java b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemFullBlock.java
index 8707ca5e9..6f9e0b958 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemFullBlock.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemFullBlock.java
@@ -7,12 +7,14 @@
 import dan200.computercraft.annotations.ForgeOverride;
 import dan200.computercraft.shared.ModRegistry;
 import net.minecraft.core.BlockPos;
+import net.minecraft.core.Direction;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.util.RandomSource;
 import net.minecraft.world.InteractionHand;
 import net.minecraft.world.InteractionResult;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.level.Level;
+import net.minecraft.world.level.LevelAccessor;
 import net.minecraft.world.level.LevelReader;
 import net.minecraft.world.level.block.Block;
 import net.minecraft.world.level.block.EntityBlock;
@@ -49,13 +51,27 @@ public final InteractionResult use(BlockState state, Level world, BlockPos pos,
 
     @Override
     @Deprecated
-    public final void neighborChanged(BlockState state, Level world, BlockPos pos, Block neighbourBlock, BlockPos neighbourPos, boolean isMoving) {
-        if (world.getBlockEntity(pos) instanceof WiredModemFullBlockEntity modem) modem.neighborChanged(neighbourPos);
+    public BlockState updateShape(BlockState state, Direction direction, BlockState neighborState, LevelAccessor level, BlockPos pos, BlockPos neighborPos) {
+        if (state.getValue(PERIPHERAL_ON) && level.getBlockEntity(pos) instanceof WiredModemFullBlockEntity modem) {
+            modem.queueRefreshPeripheral(direction);
+        }
+
+        return super.updateShape(state, direction, neighborState, level, pos, neighborPos);
+    }
+
+    @Override
+    @Deprecated
+    public final void neighborChanged(BlockState state, Level level, BlockPos pos, Block neighbourBlock, BlockPos neighbourPos, boolean isMoving) {
+        if (state.getValue(PERIPHERAL_ON) && level.getBlockEntity(pos) instanceof WiredModemFullBlockEntity modem) {
+            modem.neighborChanged(neighbourPos);
+        }
     }
 
     @ForgeOverride
-    public final void onNeighborChange(BlockState state, LevelReader world, BlockPos pos, BlockPos neighbour) {
-        if (world.getBlockEntity(pos) instanceof WiredModemFullBlockEntity modem) modem.neighborChanged(neighbour);
+    public final void onNeighborChange(BlockState state, LevelReader level, BlockPos pos, BlockPos neighbour) {
+        if (state.getValue(PERIPHERAL_ON) && level.getBlockEntity(pos) instanceof WiredModemFullBlockEntity modem) {
+            modem.neighborChanged(neighbour);
+        }
     }
 
     @Override
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemFullBlockEntity.java b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemFullBlockEntity.java
index f8c3013ca..288b0e1cd 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemFullBlockEntity.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemFullBlockEntity.java
@@ -108,14 +108,12 @@ public void clearRemoved() {
     }
 
     void neighborChanged(BlockPos neighbour) {
-        if (level.isClientSide || !isPeripheralOn()) return;
-
         for (var facing : DirectionUtil.FACINGS) {
             if (getBlockPos().relative(facing).equals(neighbour)) queueRefreshPeripheral(facing);
         }
     }
 
-    private void queueRefreshPeripheral(Direction facing) {
+    void queueRefreshPeripheral(Direction facing) {
         invalidSides |= 1 << facing.ordinal();
         TickScheduler.schedule(tickToken);
     }
diff --git a/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Computer_Test.kt b/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Computer_Test.kt
index f7800b2b5..517580964 100644
--- a/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Computer_Test.kt
+++ b/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Computer_Test.kt
@@ -11,11 +11,15 @@
 import dan200.computercraft.core.computer.ComputerSide
 import dan200.computercraft.gametest.api.*
 import dan200.computercraft.shared.ModRegistry
+import dan200.computercraft.test.core.assertArrayEquals
 import dan200.computercraft.test.core.computer.getApi
 import net.minecraft.core.BlockPos
+import net.minecraft.core.Direction
 import net.minecraft.gametest.framework.GameTest
 import net.minecraft.gametest.framework.GameTestHelper
 import net.minecraft.world.InteractionHand
+import net.minecraft.world.item.ItemStack
+import net.minecraft.world.item.Items
 import net.minecraft.world.level.block.Blocks
 import net.minecraft.world.level.block.LeverBlock
 import net.minecraft.world.level.block.RedstoneLampBlock
@@ -101,6 +105,17 @@ fun Computer_peripheral(context: GameTestHelper) = context.sequence {
         }
     }
 
+    /**
+     * Check chest peripherals are reattached with a new size.
+     */
+    @GameTest
+    fun Chest_resizes_on_change(context: GameTestHelper) = context.sequence {
+        thenOnComputer { callPeripheral("right", "size").assertArrayEquals(27) }
+        thenExecute { context.placeItemAt(ItemStack(Items.CHEST), BlockPos(2, 2, 2), Direction.WEST) }
+        thenIdle(1)
+        thenOnComputer { callPeripheral("right", "size").assertArrayEquals(54) }
+    }
+
     /**
      * Check the client can open the computer UI and interact with it.
      */
diff --git a/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Modem_Test.kt b/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Modem_Test.kt
index 85387ee76..01170422f 100644
--- a/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Modem_Test.kt
+++ b/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Modem_Test.kt
@@ -16,8 +16,11 @@
 import dan200.computercraft.test.core.computer.LuaTaskContext
 import dan200.computercraft.test.core.computer.getApi
 import net.minecraft.core.BlockPos
+import net.minecraft.core.Direction
 import net.minecraft.gametest.framework.GameTest
 import net.minecraft.gametest.framework.GameTestHelper
+import net.minecraft.world.item.ItemStack
+import net.minecraft.world.item.Items
 import net.minecraft.world.level.block.Blocks
 import org.junit.jupiter.api.Assertions.assertEquals
 import kotlin.time.Duration.Companion.milliseconds
@@ -150,6 +153,21 @@ fun Modem_keeps_cable_when_neighbour_removed(helper: GameTestHelper) = helper.se
             }
         }
     }
+
+    /**
+     * Check chest peripherals are reattached with a new size.
+     */
+    @GameTest
+    fun Chest_resizes_on_change(context: GameTestHelper) = context.sequence {
+        thenOnComputer {
+            callRemotePeripheral("minecraft:chest_0", "size").assertArrayEquals(27)
+        }
+        thenExecute { context.placeItemAt(ItemStack(Items.CHEST), BlockPos(2, 2, 2), Direction.WEST) }
+        thenIdle(1)
+        thenOnComputer {
+            callRemotePeripheral("minecraft:chest_0", "size").assertArrayEquals(54)
+        }
+    }
 }
 
 private fun LuaTaskContext.findPeripheral(type: String): String? {
@@ -169,7 +187,7 @@ fun Modem_keeps_cable_when_neighbour_removed(helper: GameTestHelper) = helper.se
         if (!peripheral.isPresent(side)) continue
         peripherals.add(side)
 
-        val hasType = peripheral.hasType(side, "modem")
+        val hasType = peripheral.hasType(side, "peripheral_hub")
         if (hasType == null || hasType[0] != true) continue
 
         val names = peripheral.call(context, ObjectArguments(side, "getNamesRemote")).await() ?: continue
@@ -180,3 +198,22 @@ fun Modem_keeps_cable_when_neighbour_removed(helper: GameTestHelper) = helper.se
     peripherals.sort()
     return peripherals
 }
+
+private suspend fun LuaTaskContext.callRemotePeripheral(name: String, method: String, vararg args: Any): Array<out Any?>? {
+    val peripheral = getApi<PeripheralAPI>()
+    if (peripheral.isPresent(name)) return peripheral.call(context, ObjectArguments(name, method, *args)).await()
+
+    for (side in ComputerSide.NAMES) {
+        if (!peripheral.isPresent(side)) continue
+
+        val hasType = peripheral.hasType(side, "peripheral_hub")
+        if (hasType == null || hasType[0] != true) continue
+
+        val isPresent = peripheral.call(context, ObjectArguments(side, "isPresentRemote", name)).await() ?: continue
+        if (isPresent[0] as Boolean) {
+            return peripheral.call(context, ObjectArguments(side, "callRemote", name, method, *args)).await()
+        }
+    }
+
+    throw IllegalArgumentException("No such peripheral $name")
+}
diff --git a/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/api/TestExtensions.kt b/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/api/TestExtensions.kt
index 2d68bb8aa..fc5977a2d 100644
--- a/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/api/TestExtensions.kt
+++ b/projects/common/src/testMod/kotlin/dan200/computercraft/gametest/api/TestExtensions.kt
@@ -19,15 +19,19 @@
 import net.minecraft.gametest.framework.*
 import net.minecraft.resources.ResourceLocation
 import net.minecraft.world.Container
+import net.minecraft.world.InteractionHand
 import net.minecraft.world.entity.Entity
 import net.minecraft.world.entity.EntityType
 import net.minecraft.world.item.ItemStack
+import net.minecraft.world.item.context.UseOnContext
 import net.minecraft.world.level.block.Blocks
 import net.minecraft.world.level.block.entity.BarrelBlockEntity
 import net.minecraft.world.level.block.entity.BlockEntity
 import net.minecraft.world.level.block.entity.BlockEntityType
 import net.minecraft.world.level.block.state.BlockState
 import net.minecraft.world.level.block.state.properties.Property
+import net.minecraft.world.phys.BlockHitResult
+import net.minecraft.world.phys.Vec3
 import org.hamcrest.Matchers
 import org.hamcrest.StringDescription
 
@@ -304,3 +308,16 @@ private fun getName(type: BlockEntityType<*>): ResourceLocation = RegistryWrappe
     container.setItem(slot, item)
     container.setChanged()
 }
+
+/**
+ * An alternative version ot [GameTestHelper.placeAt], which sets the player's held item first.
+ *
+ * This is required for compatibility with Forge, which uses the in-hand stack, rather than the stack requested.
+ */
+fun GameTestHelper.placeItemAt(stack: ItemStack, pos: BlockPos, direction: Direction) {
+    val player = makeMockPlayer()
+    player.setItemInHand(InteractionHand.MAIN_HAND, stack)
+    val absolutePos = absolutePos(pos.relative(direction))
+    val hit = BlockHitResult(Vec3.atCenterOf(absolutePos), direction, absolutePos, false)
+    stack.useOn(UseOnContext(player, InteractionHand.MAIN_HAND, hit))
+}
diff --git a/projects/common/src/testMod/resources/data/cctest/structures/computer_test.chest_resizes_on_change.snbt b/projects/common/src/testMod/resources/data/cctest/structures/computer_test.chest_resizes_on_change.snbt
new file mode 100644
index 000000000..877e24bdd
--- /dev/null
+++ b/projects/common/src/testMod/resources/data/cctest/structures/computer_test.chest_resizes_on_change.snbt
@@ -0,0 +1,138 @@
+{
+    DataVersion: 3465,
+    size: [5, 5, 5],
+    data: [
+        {pos: [0, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [0, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [0, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [0, 0, 3], state: "minecraft:polished_andesite"},
+        {pos: [0, 0, 4], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 3], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 4], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 3], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 4], state: "minecraft:polished_andesite"},
+        {pos: [3, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [3, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [3, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [3, 0, 3], state: "minecraft:polished_andesite"},
+        {pos: [3, 0, 4], state: "minecraft:polished_andesite"},
+        {pos: [4, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [4, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [4, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [4, 0, 3], state: "minecraft:polished_andesite"},
+        {pos: [4, 0, 4], state: "minecraft:polished_andesite"},
+        {pos: [0, 1, 0], state: "minecraft:air"},
+        {pos: [0, 1, 1], state: "minecraft:air"},
+        {pos: [0, 1, 2], state: "minecraft:air"},
+        {pos: [0, 1, 3], state: "minecraft:air"},
+        {pos: [0, 1, 4], state: "minecraft:air"},
+        {pos: [1, 1, 0], state: "minecraft:air"},
+        {pos: [1, 1, 1], state: "minecraft:air"},
+        {pos: [1, 1, 2], state: "minecraft:air"},
+        {pos: [1, 1, 3], state: "minecraft:air"},
+        {pos: [1, 1, 4], state: "minecraft:air"},
+        {pos: [2, 1, 0], state: "minecraft:air"},
+        {pos: [2, 1, 1], state: "minecraft:air"},
+        {pos: [2, 1, 2], state: "minecraft:chest{facing:north,type:single,waterlogged:false}", nbt: {Items: [], id: "minecraft:chest"}},
+        {pos: [2, 1, 3], state: "minecraft:air"},
+        {pos: [2, 1, 4], state: "minecraft:air"},
+        {pos: [3, 1, 0], state: "minecraft:air"},
+        {pos: [3, 1, 1], state: "minecraft:air"},
+        {pos: [3, 1, 2], state: "computercraft:computer_normal{facing:north,state:on}", nbt: {ComputerId: 1, Label: "computer_test.chest_resizes_on_change", On: 1b, id: "computercraft:computer_normal"}},
+        {pos: [3, 1, 3], state: "minecraft:air"},
+        {pos: [3, 1, 4], state: "minecraft:air"},
+        {pos: [4, 1, 0], state: "minecraft:air"},
+        {pos: [4, 1, 1], state: "minecraft:air"},
+        {pos: [4, 1, 2], state: "minecraft:air"},
+        {pos: [4, 1, 3], state: "minecraft:air"},
+        {pos: [4, 1, 4], state: "minecraft:air"},
+        {pos: [0, 2, 0], state: "minecraft:air"},
+        {pos: [0, 2, 1], state: "minecraft:air"},
+        {pos: [0, 2, 2], state: "minecraft:air"},
+        {pos: [0, 2, 3], state: "minecraft:air"},
+        {pos: [0, 2, 4], state: "minecraft:air"},
+        {pos: [1, 2, 0], state: "minecraft:air"},
+        {pos: [1, 2, 1], state: "minecraft:air"},
+        {pos: [1, 2, 2], state: "minecraft:air"},
+        {pos: [1, 2, 3], state: "minecraft:air"},
+        {pos: [1, 2, 4], state: "minecraft:air"},
+        {pos: [2, 2, 0], state: "minecraft:air"},
+        {pos: [2, 2, 1], state: "minecraft:air"},
+        {pos: [2, 2, 2], state: "minecraft:air"},
+        {pos: [2, 2, 3], state: "minecraft:air"},
+        {pos: [2, 2, 4], state: "minecraft:air"},
+        {pos: [3, 2, 0], state: "minecraft:air"},
+        {pos: [3, 2, 1], state: "minecraft:air"},
+        {pos: [3, 2, 2], state: "minecraft:air"},
+        {pos: [3, 2, 3], state: "minecraft:air"},
+        {pos: [3, 2, 4], state: "minecraft:air"},
+        {pos: [4, 2, 0], state: "minecraft:air"},
+        {pos: [4, 2, 1], state: "minecraft:air"},
+        {pos: [4, 2, 2], state: "minecraft:air"},
+        {pos: [4, 2, 3], state: "minecraft:air"},
+        {pos: [4, 2, 4], state: "minecraft:air"},
+        {pos: [0, 3, 0], state: "minecraft:air"},
+        {pos: [0, 3, 1], state: "minecraft:air"},
+        {pos: [0, 3, 2], state: "minecraft:air"},
+        {pos: [0, 3, 3], state: "minecraft:air"},
+        {pos: [0, 3, 4], state: "minecraft:air"},
+        {pos: [1, 3, 0], state: "minecraft:air"},
+        {pos: [1, 3, 1], state: "minecraft:air"},
+        {pos: [1, 3, 2], state: "minecraft:air"},
+        {pos: [1, 3, 3], state: "minecraft:air"},
+        {pos: [1, 3, 4], state: "minecraft:air"},
+        {pos: [2, 3, 0], state: "minecraft:air"},
+        {pos: [2, 3, 1], state: "minecraft:air"},
+        {pos: [2, 3, 2], state: "minecraft:air"},
+        {pos: [2, 3, 3], state: "minecraft:air"},
+        {pos: [2, 3, 4], state: "minecraft:air"},
+        {pos: [3, 3, 0], state: "minecraft:air"},
+        {pos: [3, 3, 1], state: "minecraft:air"},
+        {pos: [3, 3, 2], state: "minecraft:air"},
+        {pos: [3, 3, 3], state: "minecraft:air"},
+        {pos: [3, 3, 4], state: "minecraft:air"},
+        {pos: [4, 3, 0], state: "minecraft:air"},
+        {pos: [4, 3, 1], state: "minecraft:air"},
+        {pos: [4, 3, 2], state: "minecraft:air"},
+        {pos: [4, 3, 3], state: "minecraft:air"},
+        {pos: [4, 3, 4], state: "minecraft:air"},
+        {pos: [0, 4, 0], state: "minecraft:air"},
+        {pos: [0, 4, 1], state: "minecraft:air"},
+        {pos: [0, 4, 2], state: "minecraft:air"},
+        {pos: [0, 4, 3], state: "minecraft:air"},
+        {pos: [0, 4, 4], state: "minecraft:air"},
+        {pos: [1, 4, 0], state: "minecraft:air"},
+        {pos: [1, 4, 1], state: "minecraft:air"},
+        {pos: [1, 4, 2], state: "minecraft:air"},
+        {pos: [1, 4, 3], state: "minecraft:air"},
+        {pos: [1, 4, 4], state: "minecraft:air"},
+        {pos: [2, 4, 0], state: "minecraft:air"},
+        {pos: [2, 4, 1], state: "minecraft:air"},
+        {pos: [2, 4, 2], state: "minecraft:air"},
+        {pos: [2, 4, 3], state: "minecraft:air"},
+        {pos: [2, 4, 4], state: "minecraft:air"},
+        {pos: [3, 4, 0], state: "minecraft:air"},
+        {pos: [3, 4, 1], state: "minecraft:air"},
+        {pos: [3, 4, 2], state: "minecraft:air"},
+        {pos: [3, 4, 3], state: "minecraft:air"},
+        {pos: [3, 4, 4], state: "minecraft:air"},
+        {pos: [4, 4, 0], state: "minecraft:air"},
+        {pos: [4, 4, 1], state: "minecraft:air"},
+        {pos: [4, 4, 2], state: "minecraft:air"},
+        {pos: [4, 4, 3], state: "minecraft:air"},
+        {pos: [4, 4, 4], state: "minecraft:air"}
+    ],
+    entities: [],
+    palette: [
+        "minecraft:polished_andesite",
+        "minecraft:air",
+        "minecraft:chest{facing:north,type:single,waterlogged:false}",
+        "computercraft:computer_normal{facing:north,state:on}"
+    ]
+}
diff --git a/projects/common/src/testMod/resources/data/cctest/structures/modem_test.chest_resizes_on_change.snbt b/projects/common/src/testMod/resources/data/cctest/structures/modem_test.chest_resizes_on_change.snbt
new file mode 100644
index 000000000..b5fbf4cf8
--- /dev/null
+++ b/projects/common/src/testMod/resources/data/cctest/structures/modem_test.chest_resizes_on_change.snbt
@@ -0,0 +1,139 @@
+{
+    DataVersion: 3465,
+    size: [5, 5, 5],
+    data: [
+        {pos: [0, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [0, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [0, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [0, 0, 3], state: "minecraft:polished_andesite"},
+        {pos: [0, 0, 4], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 3], state: "minecraft:polished_andesite"},
+        {pos: [1, 0, 4], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 3], state: "minecraft:polished_andesite"},
+        {pos: [2, 0, 4], state: "minecraft:polished_andesite"},
+        {pos: [3, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [3, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [3, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [3, 0, 3], state: "minecraft:polished_andesite"},
+        {pos: [3, 0, 4], state: "minecraft:polished_andesite"},
+        {pos: [4, 0, 0], state: "minecraft:polished_andesite"},
+        {pos: [4, 0, 1], state: "minecraft:polished_andesite"},
+        {pos: [4, 0, 2], state: "minecraft:polished_andesite"},
+        {pos: [4, 0, 3], state: "minecraft:polished_andesite"},
+        {pos: [4, 0, 4], state: "minecraft:polished_andesite"},
+        {pos: [0, 1, 0], state: "minecraft:air"},
+        {pos: [0, 1, 1], state: "minecraft:air"},
+        {pos: [0, 1, 2], state: "minecraft:air"},
+        {pos: [0, 1, 3], state: "minecraft:air"},
+        {pos: [0, 1, 4], state: "minecraft:air"},
+        {pos: [1, 1, 0], state: "minecraft:air"},
+        {pos: [1, 1, 1], state: "minecraft:air"},
+        {pos: [1, 1, 2], state: "minecraft:air"},
+        {pos: [1, 1, 3], state: "minecraft:air"},
+        {pos: [1, 1, 4], state: "minecraft:air"},
+        {pos: [2, 1, 0], state: "minecraft:air"},
+        {pos: [2, 1, 1], state: "minecraft:air"},
+        {pos: [2, 1, 2], state: "minecraft:chest{facing:north,type:single,waterlogged:false}", nbt: {Items: [], id: "minecraft:chest"}},
+        {pos: [2, 1, 3], state: "minecraft:air"},
+        {pos: [2, 1, 4], state: "minecraft:air"},
+        {pos: [3, 1, 0], state: "minecraft:air"},
+        {pos: [3, 1, 1], state: "computercraft:computer_normal{facing:north,state:on}", nbt: {ComputerId: 1, Label: "modem_test.chest_resizes_on_change", On: 1b, id: "computercraft:computer_normal"}},
+        {pos: [3, 1, 2], state: "computercraft:wired_modem_full{modem:false,peripheral:true}", nbt: {PeripheralId2: 2, PeripheralId4: 0, PeripheralType2: "computer", PeripheralType4: "minecraft:chest", id: "computercraft:wired_modem_full"}},
+        {pos: [3, 1, 3], state: "minecraft:air"},
+        {pos: [3, 1, 4], state: "minecraft:air"},
+        {pos: [4, 1, 0], state: "minecraft:air"},
+        {pos: [4, 1, 1], state: "minecraft:air"},
+        {pos: [4, 1, 2], state: "minecraft:air"},
+        {pos: [4, 1, 3], state: "minecraft:air"},
+        {pos: [4, 1, 4], state: "minecraft:air"},
+        {pos: [0, 2, 0], state: "minecraft:air"},
+        {pos: [0, 2, 1], state: "minecraft:air"},
+        {pos: [0, 2, 2], state: "minecraft:air"},
+        {pos: [0, 2, 3], state: "minecraft:air"},
+        {pos: [0, 2, 4], state: "minecraft:air"},
+        {pos: [1, 2, 0], state: "minecraft:air"},
+        {pos: [1, 2, 1], state: "minecraft:air"},
+        {pos: [1, 2, 2], state: "minecraft:air"},
+        {pos: [1, 2, 3], state: "minecraft:air"},
+        {pos: [1, 2, 4], state: "minecraft:air"},
+        {pos: [2, 2, 0], state: "minecraft:air"},
+        {pos: [2, 2, 1], state: "minecraft:air"},
+        {pos: [2, 2, 2], state: "minecraft:air"},
+        {pos: [2, 2, 3], state: "minecraft:air"},
+        {pos: [2, 2, 4], state: "minecraft:air"},
+        {pos: [3, 2, 0], state: "minecraft:air"},
+        {pos: [3, 2, 1], state: "minecraft:air"},
+        {pos: [3, 2, 2], state: "minecraft:air"},
+        {pos: [3, 2, 3], state: "minecraft:air"},
+        {pos: [3, 2, 4], state: "minecraft:air"},
+        {pos: [4, 2, 0], state: "minecraft:air"},
+        {pos: [4, 2, 1], state: "minecraft:air"},
+        {pos: [4, 2, 2], state: "minecraft:air"},
+        {pos: [4, 2, 3], state: "minecraft:air"},
+        {pos: [4, 2, 4], state: "minecraft:air"},
+        {pos: [0, 3, 0], state: "minecraft:air"},
+        {pos: [0, 3, 1], state: "minecraft:air"},
+        {pos: [0, 3, 2], state: "minecraft:air"},
+        {pos: [0, 3, 3], state: "minecraft:air"},
+        {pos: [0, 3, 4], state: "minecraft:air"},
+        {pos: [1, 3, 0], state: "minecraft:air"},
+        {pos: [1, 3, 1], state: "minecraft:air"},
+        {pos: [1, 3, 2], state: "minecraft:air"},
+        {pos: [1, 3, 3], state: "minecraft:air"},
+        {pos: [1, 3, 4], state: "minecraft:air"},
+        {pos: [2, 3, 0], state: "minecraft:air"},
+        {pos: [2, 3, 1], state: "minecraft:air"},
+        {pos: [2, 3, 2], state: "minecraft:air"},
+        {pos: [2, 3, 3], state: "minecraft:air"},
+        {pos: [2, 3, 4], state: "minecraft:air"},
+        {pos: [3, 3, 0], state: "minecraft:air"},
+        {pos: [3, 3, 1], state: "minecraft:air"},
+        {pos: [3, 3, 2], state: "minecraft:air"},
+        {pos: [3, 3, 3], state: "minecraft:air"},
+        {pos: [3, 3, 4], state: "minecraft:air"},
+        {pos: [4, 3, 0], state: "minecraft:air"},
+        {pos: [4, 3, 1], state: "minecraft:air"},
+        {pos: [4, 3, 2], state: "minecraft:air"},
+        {pos: [4, 3, 3], state: "minecraft:air"},
+        {pos: [4, 3, 4], state: "minecraft:air"},
+        {pos: [0, 4, 0], state: "minecraft:air"},
+        {pos: [0, 4, 1], state: "minecraft:air"},
+        {pos: [0, 4, 2], state: "minecraft:air"},
+        {pos: [0, 4, 3], state: "minecraft:air"},
+        {pos: [0, 4, 4], state: "minecraft:air"},
+        {pos: [1, 4, 0], state: "minecraft:air"},
+        {pos: [1, 4, 1], state: "minecraft:air"},
+        {pos: [1, 4, 2], state: "minecraft:air"},
+        {pos: [1, 4, 3], state: "minecraft:air"},
+        {pos: [1, 4, 4], state: "minecraft:air"},
+        {pos: [2, 4, 0], state: "minecraft:air"},
+        {pos: [2, 4, 1], state: "minecraft:air"},
+        {pos: [2, 4, 2], state: "minecraft:air"},
+        {pos: [2, 4, 3], state: "minecraft:air"},
+        {pos: [2, 4, 4], state: "minecraft:air"},
+        {pos: [3, 4, 0], state: "minecraft:air"},
+        {pos: [3, 4, 1], state: "minecraft:air"},
+        {pos: [3, 4, 2], state: "minecraft:air"},
+        {pos: [3, 4, 3], state: "minecraft:air"},
+        {pos: [3, 4, 4], state: "minecraft:air"},
+        {pos: [4, 4, 0], state: "minecraft:air"},
+        {pos: [4, 4, 1], state: "minecraft:air"},
+        {pos: [4, 4, 2], state: "minecraft:air"},
+        {pos: [4, 4, 3], state: "minecraft:air"},
+        {pos: [4, 4, 4], state: "minecraft:air"}
+    ],
+    entities: [],
+    palette: [
+        "minecraft:polished_andesite",
+        "minecraft:air",
+        "minecraft:chest{facing:north,type:single,waterlogged:false}",
+        "computercraft:computer_normal{facing:north,state:on}",
+        "computercraft:wired_modem_full{modem:false,peripheral:true}"
+    ]
+}