found another small bug

.changeset/quiet-lions-laugh.md

@@ -0,0 +1,5 @@
+---
+'@projectstorm/react-workspaces-core': patch
+---
+
+Prevent workspace root models from being collapsed during normalization after a root-level drop split.

demo/package.json

@@ -23,15 +23,16 @@
     "typeface-open-sans": "^1.1.13"
   },
   "devDependencies": {
+    "@storybook/addon-webpack5-compiler-swc": "^4.0.3",
+    "@storybook/react-webpack5": "^10.4.6",
     "@types/lodash": "^4.17.24",
     "@types/node": "^26.1.1",
     "@types/react": "19.2.17",
     "@types/react-dom": "^19.2.3",
+    "gh-pages": "^6.3.0",
     "react-dom": "19.2.7",
     "source-map-loader": "^5.0.0",
     "storybook": "^10.4.6",
-    "@storybook/react-webpack5": "^10.4.6",
-    "@storybook/addon-webpack5-compiler-swc": "^4.0.3",
     "webpack": "^5.108.4"
   }
 }

package.json

@@ -27,7 +27,7 @@
     "build": "tsc --build && pnpm run -r build",
     "build:prod": "NODE_ENV=production pnpm build",
     "release": "pnpm build:prod && pnpm changeset publish",
-    "release:storybook": "tsc --build && cd demo && pnpm storybook:build && ./node_modules/.bin/storybook-to-ghpages --existing-output-dir .out"
+    "release:storybook": "tsc --build && cd demo && pnpm storybook:build && pnpm exec gh-pages --dist .out"
   },
   "devDependencies": {
     "babel-loader": "^10.1.1",

packages/core/src/core/WorkspaceEngine.tsx

@@ -121,6 +121,10 @@ export class WorkspaceEngine extends BaseObserver<WorkspaceEngineListener> imple
     this.rootModel
       .flatten()
       .filter((m) => m instanceof WorkspaceCollectionModel)
+      // The configured root may be re-parented while a drop creates a new
+      // outer layout. It remains the engine's stable workspace anchor and
+      // must never be removed or collapsed by collection normalization.
+      .filter((m) => m !== this.rootModel)
       .forEach((m: WorkspaceCollectionModel) => m.normalize());
   }