diff --git a/pxtlib/tilemap.ts b/pxtlib/tilemap.ts
index 653bdf328699..cee08e6eb02b 100644
--- a/pxtlib/tilemap.ts
+++ b/pxtlib/tilemap.ts
@@ -1240,14 +1240,11 @@ namespace pxt {
             }
 
             function cleanupCollection<U extends Asset>(collection: AssetCollection<U>) {
-                const inactiveAssets = collection.getSnapshot(asset => !asset.meta.displayName && asset.meta.blockIDs?.some(id => activeBlockIDs.indexOf(id) === -1));
+                const inactiveAssets = collection.getSnapshot(asset => asset.meta.blockIDs?.some(id => activeBlockIDs.indexOf(id) === -1));
                 const toRemove: Asset[] = [];
                 for (const asset of inactiveAssets) {
-                    if (asset.meta.blockIDs.length === 1) toRemove.push(asset)
-                    else {
-                        asset.meta.blockIDs = asset.meta.blockIDs.filter(id => activeBlockIDs.indexOf(id) !== -1);
-                        if (asset.meta.blockIDs.length === 0) toRemove.push(asset);
-                    }
+                    asset.meta.blockIDs = asset.meta.blockIDs.filter(id => activeBlockIDs.indexOf(id) !== -1);
+                    if (!asset.meta.displayName && asset.meta.blockIDs.length === 0) toRemove.push(asset);
                 }
                 for (const asset of toRemove) {
                     collection.removeByID(asset.id);
diff --git a/webapp/src/components/assetEditor/assetSidebar.tsx b/webapp/src/components/assetEditor/assetSidebar.tsx
index 7e557156876f..424be125cb4c 100644
--- a/webapp/src/components/assetEditor/assetSidebar.tsx
+++ b/webapp/src/components/assetEditor/assetSidebar.tsx
@@ -54,6 +54,10 @@ class AssetSidebarImpl extends React.Component<AssetSidebarProps, AssetSidebarSt
             const project = pxt.react.getTilemapProject();
             const canEdit = !isGalleryAsset;
             const canCopy = asset?.type != pxt.AssetType.Tilemap && asset?.type != pxt.AssetType.Animation;
+            const blocksEditor = getBlocksEditor();
+            if (blocksEditor?.editor) {
+                project.removeInactiveBlockAssets(blocksEditor.editor.getAllBlocks(false).map(block => block.id));
+            }
             const canDelete = !isGalleryAsset && !project.isAssetUsed(asset, pkg.mainEditorPkg().files);
 
             this.setState({ canEdit, canCopy, canDelete });