The topbar is icons only: the leading Project dropdown, the Scene picker and the labelled Play/Pause buttons are gone and in their place stand five icon buttons - menu, undo, redo on the left, play and pause in the middle - while Notice, the save state, fps and the Account menu keep the right side; the Play button swaps its icon for a stop square while the project runs and Pause swaps for a second play sign while it is held (Button.setIcon()), and iconSpace() drops the gap between icon and label when a button has no label, which is what kept a 24 px icon button 3 px off its own centre; the menu carries New project, Open project..., a separator and Project settings..., where the picker (src/editor/OpenProjectDialog.ts) preselects the open project and marks it "open", opens on a double click and puts Delete on the left of Cancel and Open - it closes itself before it asks whether to delete, because two modals on top of each other would have left the question standing over a list it no longer speaks about - and the settings dialog (src/editor/ProjectSettingsDialog.ts) holds the name, the "Play starts" switch (Start scene / Active scene, a preference of this browser and so no command) and the collision layers from #152, which retires CollisionLayersDialog.ts and the "Collision layers..." entry; what Apply actually writes is the pure function settingsChanges(), so renaming and the layers are each their own undo step and each drop out when nothing differs; the Scene dropdown falls away without replacement, the active scene is switched by double clicking it in the Assets panel, which is the way that was there anyway; new module 46 runs last with 9 checks (no label left in the bar, the run buttons in edit mode, the four menu entries, the picker with the open project preselected, Cancel leaving the project standing, the settings dialog on the state of the project, renaming with undo and redo through the icon buttons) and it neither opens nor deletes a project, because that would pull the project out from under every earlier module; modules 8, 18 and 35 and the harness follow the new bar, 6 unit tests cover settingsChanges and 3 the icons (#183)

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/editor/debugHook.ts

@@ -209,8 +209,19 @@ export function installDebugHook(app: Application, state: EditorState, editor: E
     /** The project's collision layers (#152), and the names the open dialog holds (null when shut). */
     collisionLayers: () => ({
       project: [...state.project.collisionLayers],
-      dialog: editor.collisionLayersDialog()?.layerNames() ?? null,
+      dialog: editor.projectSettingsDialog()?.layerNames() ?? null,
     }),
+    /** The "Project settings" dialog (#183): name and start-scene switch as its fields stand. */
+    projectSettings: () => editor.projectSettingsDialog()?.values() ?? null,
+    /** Where to click the start-scene switch inside that dialog. */
+    projectSettingsPlayFromAt: () => {
+      const dialog = editor.projectSettingsDialog();
+      return dialog ? centreOf(dialog.playFromControl) : null;
+    },
+    /** The "Open project" dialog (#183): the projects it lists and the row picked. */
+    projectPicker: () => editor.projectPickerDialog()?.info() ?? null,
+    /** Where to click a project's row in that dialog. */
+    projectPickerRowAt: (id: string) => editor.projectPickerDialog()?.rowPosition(id) ?? null,
     /** The dividers left and right of the centre column – dragging them narrows the tab row. */
     panelSplitters: () => ({ left: centreOf(editor.leftSplitter), right: centreOf(editor.rightSplitter) }),
     /** The left column: asset panel on top, scene objects below, and the divider between them. */
@@ -594,11 +605,12 @@ export function installDebugHook(app: Application, state: EditorState, editor: E
     },
     world: () => editor.worldSnapshot(),
     playInfo: () => editor.playInfo(),
-    /** The start-scene switch: what it says, and where to click it (its caption is elided). */
+    /** Which scene Play would start, and under which of the two rules (#183: set in the settings). */
     playFrom: () => editor.playFromInfo(),
-    playFromAt: () => centreOf(editor.playFromButton),
-    /** The scene selector: where it is, and whether it takes a click (it does, play mode or not). */
-    sceneSelect: () => ({ ...centreOf(editor.sceneButton), enabled: editor.sceneButton.enabled }),
+    /** The two run buttons of the top bar: the picture each wears, and whether it takes a click. */
+    runButtons: () => editor.runButtons(),
+    /** Where to click one of the five icon buttons: menu, undo, redo, play, pause. */
+    toolbarAt: (name: keyof Editor['toolbarControls']) => centreOf(editor.toolbarControls[name]),
     /** Behaviors running without Play (`Run in editor`), and how long they have been at it. */
     editorRun: () => editor.editorRunInfo(),
     physics: () => physicsStatus(),