diff --git a/frontend/src/App.tsx b/frontend/src/App.tsx
index 2e9713e..d262891 100644
--- a/frontend/src/App.tsx
+++ b/frontend/src/App.tsx
@@ -55,7 +55,7 @@ import { buildProxmoxClusterEdges } from '@/components/proxmox/clusterEdges'
 const STANDALONE = import.meta.env.VITE_STANDALONE === 'true'
 
 export default function App() {
-  const { loadCanvas, applyLayout, markSaved, markUnsaved, hasUnsavedChanges, selectedNodeId, selectedNodeIds, addNode, updateNode, deleteNode, onConnect, updateEdge, deleteEdge, setProxmoxContainerMode, setNodeZIndex, editingGroupRectId, setEditingGroupRectId, editingTextId, setEditingTextId, nodes, edges, snapshotHistory, undo, redo, addToGroup, addToContainer, floorMap, setFloorMap } = useCanvasStore()
+  const { loadCanvas, applyLayout, markSaved, markUnsaved, hasUnsavedChanges, editSeq, selectedNodeId, selectedNodeIds, addNode, updateNode, deleteNode, onConnect, updateEdge, deleteEdge, setProxmoxContainerMode, setNodeZIndex, editingGroupRectId, setEditingGroupRectId, editingTextId, setEditingTextId, nodes, edges, snapshotHistory, undo, redo, addToGroup, addToContainer, floorMap, setFloorMap } = useCanvasStore()
   const canvasRef = useRef<HTMLDivElement>(null)
   const { isAuthenticated } = useAuthStore()
   const { activeTheme, setTheme, customStyle, setCustomStyle } = useThemeStore()
@@ -142,7 +142,10 @@ export default function App() {
     delaySeconds: autosave.delay,
     hasUnsavedChanges,
     designId: loadedDesignId,
-    changeSignals: [nodes, edges],
+    // Debounce resets on each real user edit (editSeq), not on raw nodes/edges
+    // identity — live status polling churns those arrays without a user edit and
+    // would otherwise keep re-arming (and starving) the timer during monitoring.
+    changeSignals: [editSeq],
     getLiveDesignId: () => loadedDesignIdRef.current,
     onSave: (designId) => { void handleSaveRef.current(designId, { silent: true }) },
   })
diff --git a/frontend/src/stores/__tests__/canvasStore/nodes.test.ts b/frontend/src/stores/__tests__/canvasStore/nodes.test.ts
index 7bc3412..e2239f6 100644
--- a/frontend/src/stores/__tests__/canvasStore/nodes.test.ts
+++ b/frontend/src/stores/__tests__/canvasStore/nodes.test.ts
@@ -9,6 +9,7 @@ function resetStore() {
     nodes: [],
     edges: [],
     hasUnsavedChanges: false,
+    editSeq: 0,
     selectedNodeId: null,
     selectedNodeIds: [],
     editingGroupRectId: null,
@@ -97,6 +98,34 @@ describe('canvasStore — nodes', () => {
     expect(useCanvasStore.getState().hasUnsavedChanges).toBe(false)
   })
 
+  it('editSeq bumps on a real user edit but not on status/select/measure churn', () => {
+    const seq = () => useCanvasStore.getState().editSeq
+
+    // Real edit bumps.
+    const before = seq()
+    useCanvasStore.getState().addNode(makeNode('n1'))
+    expect(seq()).toBe(before + 1)
+
+    // Live status update: no bump (not a user edit).
+    const afterAdd = seq()
+    useCanvasStore.getState().setNodeStatus('n1', { status: 'online' })
+    expect(seq()).toBe(afterAdd)
+
+    // Select-only change: no bump.
+    useCanvasStore.getState().onNodesChange([{ id: 'n1', type: 'select', selected: true }])
+    expect(seq()).toBe(afterAdd)
+
+    // Initial dimensions measure: no bump.
+    useCanvasStore.getState().onNodesChange([
+      { id: 'n1', type: 'dimensions', dimensions: { width: 120, height: 40 } },
+    ])
+    expect(seq()).toBe(afterAdd)
+
+    // Another real edit bumps again.
+    useCanvasStore.getState().updateNode('n1', { label: 'renamed' })
+    expect(seq()).toBe(afterAdd + 1)
+  })
+
   it('setEditingTextId sets and clears editing text id', () => {
     const { setEditingTextId } = useCanvasStore.getState()
     setEditingTextId('t1')
diff --git a/frontend/src/stores/canvasStore.ts b/frontend/src/stores/canvasStore.ts
index c8c8c91..519d54d 100644
--- a/frontend/src/stores/canvasStore.ts
+++ b/frontend/src/stores/canvasStore.ts
@@ -109,6 +109,14 @@ interface CanvasState {
   nodes: Node<NodeData>[]
   edges: Edge<EdgeData>[]
   hasUnsavedChanges: boolean
+  /**
+   * Monotonic counter incremented on every real user edit (auto-bumped whenever
+   * an action sets hasUnsavedChanges to true). Consumers that need to react to
+   * *edits specifically* — e.g. the autosave debounce — key off this instead of
+   * the nodes/edges array identity, which also churns on live status updates and
+   * selection changes that must NOT reset the debounce.
+   */
+  editSeq: number
   selectedNodeId: string | null
   selectedNodeIds: string[]
   scanEventTs: number
@@ -187,10 +195,33 @@ interface CanvasState {
   applyAllCustomStyles: (def: CustomStyleDef) => void
 }
 
-export const useCanvasStore = create<CanvasState>((set) => ({
+export const useCanvasStore = create<CanvasState>((rawSet) => {
+  // Wrap set so any update that flips hasUnsavedChanges to true also bumps
+  // editSeq. This centralises the "an edit happened" signal instead of touching
+  // every one of the ~two dozen mutating actions. Actions that update state
+  // without dirtying (setNodeStatus, markSaved, loadCanvas, selection) omit
+  // hasUnsavedChanges or set it false, so they never bump the counter.
+  const set: typeof rawSet = ((partial, replace) => {
+    rawSet((state) => {
+      const next = typeof partial === 'function'
+        ? (partial as (s: CanvasState) => Partial<CanvasState>)(state)
+        : partial
+      if (
+        next &&
+        typeof next === 'object' &&
+        (next as Partial<CanvasState>).hasUnsavedChanges === true &&
+        !('editSeq' in next)
+      ) {
+        return { ...next, editSeq: state.editSeq + 1 }
+      }
+      return next
+    }, replace as false | undefined)
+  }) as typeof rawSet
+  return {
   nodes: [],
   edges: [],
   hasUnsavedChanges: false,
+  editSeq: 0,
   selectedNodeId: null,
   selectedNodeIds: [],
   editingGroupRectId: null,
@@ -347,19 +378,26 @@ export const useCanvasStore = create<CanvasState>((set) => ({
       // they don't follow a moved node on their own. Translate them by the same
       // delta the node moved so a clean routing stays clean after a drag (#279).
       const edges = translateWaypointsForMovedNodes(changes, state.nodes, nodes, state.edges)
+      // Only set hasUnsavedChanges when a real edit occurred, so the set() wrapper
+      // bumps editSeq only then. Selection- or measure-only changes leave the flag
+      // untouched (carried over) and must not reset the autosave debounce.
+      const edited = changes.some(isUserNodeEdit)
       return {
         nodes,
         edges,
         selectedNodeIds,
-        hasUnsavedChanges: state.hasUnsavedChanges || changes.some(isUserNodeEdit),
+        ...(edited ? { hasUnsavedChanges: true } : {}),
       }
     }),
 
   onEdgesChange: (changes) =>
-    set((state) => ({
-      edges: applyEdgeChanges(changes, state.edges),
-      hasUnsavedChanges: state.hasUnsavedChanges || changes.some((c) => c.type !== 'select'),
-    })),
+    set((state) => {
+      const edited = changes.some((c) => c.type !== 'select')
+      return {
+        edges: applyEdgeChanges(changes, state.edges),
+        ...(edited ? { hasUnsavedChanges: true } : {}),
+      }
+    }),
 
   onConnect: (connection) =>
     set((state) => {
@@ -1013,4 +1051,5 @@ export const useCanvasStore = create<CanvasState>((set) => ({
       })
       return { nodes, edges, hasUnsavedChanges: true }
     }),
-}))
+  }
+})