diff --git a/headless/README.md b/headless/README.md
index 771424f..a3c3169 100644
--- a/headless/README.md
+++ b/headless/README.md
@@ -333,7 +333,7 @@ claim of constant-time full-frame updates or complete region-based drawing.
 array, with byte cursors, bounded record payloads, structural depth limits and
 abort/yield checks. It uses parserVersion 3 and can feed a host-managed generic
 ImportRunner. It does not yet interpret the exported document envelope, and
-ProjectEngine now accepts native record arrays through `imports.startJsonArray(bytes, canvasId)`; the file picker routes `.json` to it. Exported document envelopes are still unsupported.
+ProjectEngine now accepts native record arrays through `imports.startJsonArray(bytes, canvasId)`; the file picker routes `.json` to it. Exported document envelopes use the separate `imports.startDocument` path described below.
 A malformed structural tail ends with an explicit failure; previously emitted
 records remain available. Empty source bytes reject, while `[]` is a valid empty
 array. Array record errors are distinct from document schema/reference failures.
@@ -344,3 +344,14 @@ and commit boundary as NDJSON. Such roots use recovery envelope 14; readers acce
 1–14 and reject 15. Downgrading an array-bearing image to 13 rejects. This changes
 neither IndexedDB schema v4 nor the server wire protocol. Native array items have
 the same `{kind,key,record}` schema as NDJSON; `$target` denotes the chosen canvas.
+
+`imports.startDocument(bytes, canvasId)` accepts the toolbar's exported document
+format v1. The JSON picker distinguishes object envelopes from record arrays.
+Source canvas ownership and references map to fresh IDs; its root maps to the
+explicit target, and tombstones are not copied into the target. The original
+file/digest and parserVersion 4 persist; the ordinal cursor resumes against the
+same indexed bytes. Document jobs use recovery v15 (readers accept 1–15, reject
+16), without changing DB v4 or the wire protocol. Current resource-bearing records
+report `import_resource_authorization_required`; other records can import with an
+explicit partial result. This is not complete asset round-trip support. Preparation
+still scans the envelope before progressive payload decoding and insertion.
diff --git a/src/components/canvas/headless-imports.tsx b/src/components/canvas/headless-imports.tsx
index 3b3ede3..7fcb2f5 100644
--- a/src/components/canvas/headless-imports.tsx
+++ b/src/components/canvas/headless-imports.tsx
@@ -7,7 +7,7 @@ import { IconButton } from "@/components/ui/icon-button";
 import { errorText } from "@/lib/api";
 import styles from "./canvas.module.css";
 
-const reason = (code: string) => ({ invalid_json_array: "JSON 记录数组格式错误", incomplete_json_array: "JSON 数组尾部不完整", json_nesting_limit: "JSON 嵌套层数过多", invalid_json: "记录格式错误", invalid_json_value: "记录包含不支持的数据", invalid_utf8: "文件编码不是 UTF-8", record_too_large: "单条记录过大", unresolved_dependency: "引用的记录未加入", invalid_native_import_record: "不是画布记录", import_component_unavailable: "元素类型暂不支持", invalid_geometry: "元素尺寸不合法", invalid_endpoint: "连线端点已不存在", duplicate_import_source_key: "记录标识重复", import_source_unavailable: "导入源文件不可用", import_source_changed: "源文件内容与保存时不一致，任务已暂停", import_source_integrity_unavailable: "旧任务缺少源内容校验，无法安全继续；已加入内容保留", import_source_integrity_missing: "源校验记录缺失，任务已暂停", import_source_integrity_interpreter_unavailable: "源校验版本暂不支持", import_target_missing: "目标分区已不存在", import_target_changed: "目标分区已改变", import_dependency_changed: "引用对象已删除或恢复为新版本", dependency_capacity: "等待引用过多，请调整文件顺序", copy_external_changed: "原图引用已删除、移动或恢复为新版本", invalid_duplicate_source: "复制源数据不可用", invalid_copy_snapshot: "复制快照不可用", invalid_copy_preparation: "复制准备记录不可用", copy_interpreter_changed: "复制规则已变化，需要重新复制", invalid_import_source: "文件过大或格式不支持" } as Record<string,string>)[code] ?? "这条记录暂时无法加入";
+const reason = (code: string) => ({ import_resource_authorization_required: "资源需要重新授权，此记录尚未加入", invalid_document_import: "导出文档结构不合法", invalid_json_array: "JSON 记录数组格式错误", incomplete_json_array: "JSON 数组尾部不完整", json_nesting_limit: "JSON 嵌套层数过多", invalid_json: "记录格式错误", invalid_json_value: "记录包含不支持的数据", invalid_utf8: "文件编码不是 UTF-8", record_too_large: "单条记录过大", unresolved_dependency: "引用的记录未加入", invalid_native_import_record: "不是画布记录", import_component_unavailable: "元素类型暂不支持", invalid_geometry: "元素尺寸不合法", invalid_endpoint: "连线端点已不存在", duplicate_import_source_key: "记录标识重复", import_source_unavailable: "导入源文件不可用", import_source_changed: "源文件内容与保存时不一致，任务已暂停", import_source_integrity_unavailable: "旧任务缺少源内容校验，无法安全继续；已加入内容保留", import_source_integrity_missing: "源校验记录缺失，任务已暂停", import_source_integrity_interpreter_unavailable: "源校验版本暂不支持", import_target_missing: "目标分区已不存在", import_target_changed: "目标分区已改变", import_dependency_changed: "引用对象已删除或恢复为新版本", dependency_capacity: "等待引用过多，请调整文件顺序", copy_external_changed: "原图引用已删除、移动或恢复为新版本", invalid_duplicate_source: "复制源数据不可用", invalid_copy_snapshot: "复制快照不可用", invalid_copy_preparation: "复制准备记录不可用", copy_interpreter_changed: "复制规则已变化，需要重新复制", invalid_import_source: "文件过大或格式不支持" } as Record<string,string>)[code] ?? "这条记录暂时无法加入";
 
 export function HeadlessImports({ engine, canvasId }: { engine: ProjectEngine; canvasId: string }) {
   const subscribe = useCallback((notify: () => void) => engine.editor.subscribe(notify), [engine]);
@@ -18,9 +18,9 @@ export function HeadlessImports({ engine, canvasId }: { engine: ProjectEngine; c
   const control = (work: Promise<void>) => { void work.then(() => { if (scope.current.engine === engine && scope.current.canvasId === canvasId) setError(""); }).catch(error => { if (scope.current.engine === engine && scope.current.canvasId === canvasId) setError(errorText(error)); }); };
   return <aside className={styles.importPanel} aria-label="画布导入">
     <div className={styles.importActions}><IconButton icon={FolderInput} label="导入画布记录" disabled={!engine.imports.canStart(canvasId).enabled} onClick={() => input.current?.click()} /><span>NDJSON / JSON 记录数组</span></div>
-    <input data-canvas-import ref={input} type="file" accept=".ndjson,.jsonl,.json,application/json,application/x-ndjson" hidden onChange={event => {
+    <input data-canvas-import ref={input} type="file" accept=".ndjson,.jsonl,.json,application/json,application/x-ndjson" hidden onChange={async event => {
       const file = event.target.files?.[0]; event.target.value = ""; if (!file) return;
-      try { if(file.name.toLowerCase().endsWith('.json'))engine.imports.startJsonArray(file,canvasId);else engine.imports.startNdjson(file,canvasId); setOpen(true); setError(""); } catch (error) { setError(errorText(error)); }
+      try { if(file.name.toLowerCase().endsWith('.json')){const before=engine.getSnapshot().document,target=before.canvases.get(canvasId),parent=JSON.stringify(target?.parent),entry=target?.parent?before.elements.get(target.parent.entryElementId)?.incarnation:undefined;const prefix=(await file.slice(0,65536).text()).trimStart()[0];if(scope.current.engine!==engine||scope.current.canvasId!==canvasId)return;const current=engine.getSnapshot().document,now=current.canvases.get(canvasId);if(!target||!now||JSON.stringify(now.parent)!==parent||(now.parent?current.elements.get(now.parent.entryElementId)?.incarnation:undefined)!==entry)throw Error('import_target_changed');if(prefix==='{')engine.imports.startDocument(file,canvasId);else if(prefix==='[')engine.imports.startJsonArray(file,canvasId);else throw Error('invalid_import_source');}else engine.imports.startNdjson(file,canvasId); setOpen(true); setError(""); } catch (error) { if(scope.current.engine===engine&&scope.current.canvasId===canvasId)setError(errorText(error)); }
     }} />
     {jobs.length > 0 && <details open={open} onToggle={event => setOpen(event.currentTarget.open)}><summary>导入与复制任务 · {jobs.some(job => job.status === "preparing") && "正在准备复制 · "}{jobs.reduce((count, job) => count + job.committedSourceKeys.length, 0)} 项已加入</summary>
       {jobs.map((job, index) => <section className={styles.importJob} key={job.id} aria-label={`导入任务 ${index + 1}`}>
diff --git a/src/lib/canvas-runtime/engine.ts b/src/lib/canvas-runtime/engine.ts
index c26374a..d8a2729 100644
--- a/src/lib/canvas-runtime/engine.ts
+++ b/src/lib/canvas-runtime/engine.ts
@@ -18,6 +18,7 @@ import { planDuplicateAsync, planDuplicateResumable, prepareDuplicateStream } fr
 import type { DigestPort } from './digest-pool.ts';
 import { importSourceDigest } from './import-integrity.ts';
 import { encodeDuplicateSource, prepareDuplicateImport, assertDuplicateExternal } from './import-duplicate.ts';
+import {openDocumentImportSource} from './import-document.ts';
 import {createJsonArrayImportSource} from './import-json-array.ts';
 import { createImportJob, createImportRunner, createNdjsonImportSource, type ImportJob } from './imports.ts';
 import { assertNativeImportDependencies, assertNativeImportTarget, prepareNativeImport } from './import-native.ts';
@@ -670,9 +671,9 @@ export async function openProjectEngine(options: EngineOptions) {
       if(importRunners.has(id)){void importRunners.get(id)!.start();return Promise.resolve();}
       deferredImportLoads.delete(id);
       let expectedFingerprint=getImport(id).sourceFingerprint;
-      const preparationController=new AbortController();if(['duplicate-snapshot','duplicate-plan'].includes(getImport(id).source?.kind??''))preparationControllers.set(id,preparationController);
+      const preparationController=new AbortController();if(['native-document','duplicate-snapshot','duplicate-plan'].includes(getImport(id).source?.kind??''))preparationControllers.set(id,preparationController);
       const task=(async()=>{
-        let job=getImport(id),source=job.source;if(!source||!['native-json-array','native-ndjson','duplicate-ndjson','duplicate-snapshot','duplicate-plan'].includes(source.kind)||job.parserVersion!==(source.kind==='native-json-array'?3:source.kind==='duplicate-plan'?2:1))throw fault('import_interpreter_unavailable');
+        let job=getImport(id),source=job.source;if(!source||!['native-document','native-json-array','native-ndjson','duplicate-ndjson','duplicate-snapshot','duplicate-plan'].includes(source.kind)||job.parserVersion!==(source.kind==='native-document'?4:source.kind==='native-json-array'?3:source.kind==='duplicate-plan'?2:1))throw fault('import_interpreter_unavailable');
         let bytes=fileWrites.get(source.fileId)??await options.storage.readFile(leader,source.fileId);
         if(closing||closed)return;
         const latest=getImport(id);if(latest.sourceFingerprint!==job.sourceFingerprint||latest.source?.fileId!==source.fileId||['completed','partial','cancelled'].includes(latest.status))return;
@@ -688,7 +689,7 @@ export async function openProjectEngine(options: EngineOptions) {
         if(source.kind==='duplicate-snapshot'){if(preparationController.signal.aborted||importHolds.size||latest.status!=='preparing')return;const materialized=await materializeCopy(id,bytes,preparationController);job=materialized.job;source=job.source!;bytes=materialized.bytes;copyDocument=materialized.document;indexed=materialized.indexed;expectedFingerprint=job.sourceFingerprint;}
         if(source.kind==='duplicate-plan'&&source.snapshotVersion===2){indexed??=await openIndexedCopySnapshot(bytes,options.scope.projectId,options.registry,preparationController.signal);copyDocument=indexed.document;}
         if(source.kind==='duplicate-plan'&&copyDocument)validateLoadingCopySource(editor.getSnapshot(),job,copyDocument);
-        const importSource=source.kind==='duplicate-plan'?createDuplicatePlanSource(copyDocument??await decodeCopySnapshot(bytes,options.scope.projectId,options.registry,preparationController.signal),options.registry,source.plan!,job.sourceFingerprint,indexed?.readElement):source.kind==='native-json-array'?createJsonArrayImportSource({bytes,fingerprint:job.sourceFingerprint}):createNdjsonImportSource({bytes,fingerprint:job.sourceFingerprint});
+        const importSource=source.kind==='duplicate-plan'?createDuplicatePlanSource(copyDocument??await decodeCopySnapshot(bytes,options.scope.projectId,options.registry,preparationController.signal),options.registry,source.plan!,job.sourceFingerprint,indexed?.readElement):source.kind==='native-document'?await openDocumentImportSource({bytes,fingerprint:job.sourceFingerprint,signal:preparationController.signal}):source.kind==='native-json-array'?createJsonArrayImportSource({bytes,fingerprint:job.sourceFingerprint}):createNdjsonImportSource({bytes,fingerprint:job.sourceFingerprint});
         if(closing||closed||preparationController.signal.aborted||getImport(id).generation!==job.generation)return;
         if(importHolds.size){deferredImportLoads.add(id);return;}
         const runner=createImportRunner({optimisticLocal:true,awaitDurabilityBudget:stage=>pending.size>=32||stage!=='parsed'&&persistenceFailed?persist():undefined,source:importSource,getJob:()=>getImport(id),createId,
@@ -705,12 +706,12 @@ export async function openProjectEngine(options: EngineOptions) {
       })().catch(error=>{if(preparationController.signal.aborted)return;if(!closing&&!closed){try{const job=getImport(id);if(job.sourceFingerprint!==expectedFingerprint||['completed','partial','cancelled','paused'].includes(job.status))return;publishImport(freeze({...job,generation:job.generation+1,status:'paused',error:(error as {code?:string}).code??'import_failed'}),job.generation);}catch{/* Recovery/identity fences retain the original job. */}report(error);}}).finally(()=>{preparationControllers.delete(id);importLoads.delete(id);if(!['running','preparing'].includes(getImport(id).status))deferredImportLoads.delete(id);if(!closing&&!closed&&!importHolds.size&&deferredImportLoads.delete(id)&&!importRunners.has(id)&&['running','preparing'].includes(getImport(id).status))queueMicrotask(()=>{if(!closing&&!closed)void loadImport(id);});});
       importLoads.set(id,task);return task;
     }
-    function startNativeImport(bytes:Blob,targetCanvasId:Id,format:'ndjson'|'json-array'):Id{
-        if(!['ndjson','json-array'].includes(format))throw fault('import_interpreter_unavailable');
+    function startNativeImport(bytes:Blob,targetCanvasId:Id,format:'ndjson'|'json-array'|'document'):Id{
+        if(!['ndjson','json-array','document'].includes(format))throw fault('import_interpreter_unavailable');
         assertImportWritable();const loadingAdmission=loadingImportAdmission(editor.getSnapshot(),targetCanvasId);const permission=options.policy?.({type:'changes.apply',changes:[]},editor.getSnapshot().document);if(permission&&!permission.enabled)throw fault(permission.code,permission.targets);const canvas=editor.getSnapshot().document.canvases.get(targetCanvasId);if(!canvas)throw fault('canvas_not_loaded',[targetCanvasId]);if(!(bytes instanceof Blob)||bytes.size>64*1024*1024)throw fault('invalid_import_source');
         const id=createId(),fileId=createId(),current=editor.getSnapshot().runtime;if(!id||!fileId||id===fileId||current.imports?.has(id)||current.resources.has(fileId)||current.orphanFiles?.has(fileId)||fileWrites.has(fileId)||importFiles(current.imports).has(fileId))throw fault('import_identity_conflict');
         const entry=canvas.parent?editor.getSnapshot().document.elements.get(canvas.parent.entryElementId)!:undefined;
-        const job=freeze({...createImportJob({id,projectId:options.scope.projectId,sourceFingerprint:`local-file:${fileId}:${bytes.size}`,parserVersion:format==='json-array'?3:1,source:{...(loadingAdmission?{loadingAdmission}:{}),kind:format==='json-array'?'native-json-array':'native-ndjson',name:((bytes as Blob&{name?:string}).name||'画布数据').slice(0,255),fileId,byteLength:bytes.size,targetCanvasId,...(entry?{targetEntry:{id:entry.id,incarnation:entry.incarnation}}:{})}}),status:'running' as const});
+        const job=freeze({...createImportJob({id,projectId:options.scope.projectId,sourceFingerprint:`local-file:${fileId}:${bytes.size}`,parserVersion:format==='document'?4:format==='json-array'?3:1,source:{...(loadingAdmission?{loadingAdmission}:{}),kind:format==='document'?'native-document':format==='json-array'?'native-json-array':'native-ndjson',name:((bytes as Blob&{name?:string}).name||'画布数据').slice(0,255),fileId,byteLength:bytes.size,targetCanvasId,...(entry?{targetEntry:{id:entry.id,incarnation:entry.incarnation}}:{})}}),status:'running' as const});
         fileWrites.set(fileId,bytes);
         const result=editor.updateRuntime(previous=>{const jobs=new Map(previous.imports??[]);jobs.set(id,job);return Object.freeze({...previous,imports:readMap(jobs)});});
         if(result.status==='rejected'){fileWrites.delete(fileId);throw fault(result.code,result.targets);}void loadImport(id);return id;
@@ -721,6 +722,7 @@ export async function openProjectEngine(options: EngineOptions) {
       canDuplicate(selection:readonly Target[],settings:{viewCanvasId?:Id}={}){try{assertImportWritable();if(collectionReservations.size)throw fault('resource_collection_in_progress',[...collectionReservations]);const snapshot=editor.getSnapshot(),permission=options.policy?.({type:'changes.apply',changes:[]},snapshot.document);if(permission&&!permission.enabled)throw fault(permission.code,permission.targets);if(!selection.length)throw fault('empty_copy_selection');for(const selected of selection){const element=snapshot.document.elements.get(selected.id);if(!element||element.incarnation!==selected.incarnation)throw fault('stale_incarnation',[selected.id]);}const target=settings.viewCanvasId??snapshot.document.elements.get(selection[0].id)!.ownerCanvasId;if(!snapshot.document.canvases.has(target))throw fault('canvas_not_loaded',[target]);loadingImportAdmission(snapshot,target,selection);return{enabled:true as const};}catch(error){const result=reject(error);return{enabled:false as const,code:result.code,targets:result.targets};}},
       openSource:openImportSource,
       startNdjson:(bytes:Blob,targetCanvasId:Id)=>startNativeImport(bytes,targetCanvasId,'ndjson'),
+      startDocument:(bytes:Blob,targetCanvasId:Id)=>startNativeImport(bytes,targetCanvasId,'document'),
       startJsonArray:(bytes:Blob,targetCanvasId:Id)=>startNativeImport(bytes,targetCanvasId,'json-array'),
       async duplicate(selection:readonly Target[],settings:{readonly worldOffset?:Point;readonly signal?:AbortSignal;readonly viewCanvasId?:Id}={}):Promise<Id>{
         assertImportWritable();if(collectionReservations.size)throw fault('resource_collection_in_progress',[...collectionReservations]);
diff --git a/src/lib/canvas-runtime/import-native.ts b/src/lib/canvas-runtime/import-native.ts
index 6b9583c..5bd6434 100644
--- a/src/lib/canvas-runtime/import-native.ts
+++ b/src/lib/canvas-runtime/import-native.ts
@@ -27,7 +27,7 @@ export function prepareNativeImport(line:ImportLine,job:ImportJob,reserve:(key:s
   const record=clone(raw.record) as Record<string,Json>;if(record.id!==raw.key)throw fault('import_source_identity_mismatch');
   const dependencies=new Set<string>(),elementIds=new Map<Id,Id>(),canvasIds=new Map<Id,Id>();
   const element=(id:Json):Id=>{if(typeof id!=='string'||!id)throw fault('invalid_import_reference');const key=`element:${id}`;dependencies.add(key);const mapped=reserve(key);elementIds.set(id,mapped);return mapped;};
-  const owner=(id:Json):Id=>{if(id==='$target'){canvasIds.set('$target',source.targetCanvasId);return source.targetCanvasId;}if(typeof id!=='string'||!id)throw fault('invalid_import_reference');const key=`canvas:${id}`;dependencies.add(key);const mapped=reserve(key);canvasIds.set(id,mapped);return mapped;};
+  const owner=(id:Json):Id=>{if(id==='$target'||source.kind==='native-document'&&id===raw.sourceRootId){canvasIds.set(id as string,source.targetCanvasId);return source.targetCanvasId;}if(typeof id!=='string'||!id)throw fault('invalid_import_reference');const key=`canvas:${id}`;dependencies.add(key);const mapped=reserve(key);canvasIds.set(id,mapped);return mapped;};
   const key=`${raw.kind}:${raw.key}`,id=reserve(key);
   if(raw.kind==='canvas'){
     const parent=record.parent as Record<string,Json>|null;
@@ -37,6 +37,7 @@ export function prepareNativeImport(line:ImportLine,job:ImportJob,reserve:(key:s
   }
   const original=record as unknown as ElementRecord,definition=registry.components.get(original.componentId);
   if(registry.resolve(original)!=='known'||!definition?.copy||!original.data||typeof original.data!=='object'||Array.isArray(original.data))throw fault('import_component_unavailable');
+  if(source.kind==='native-document'&&definition.resourceFields?.some(key=>original.data[key]!==undefined&&original.data[key]!==null))throw fault('import_resource_authorization_required');
   for(const ref of definition.copy.references)for(const item of copyReferenceIds(original.data,ref)){if(ref.target==='element')element(item);else owner(item);}
   const after={...record,id,incarnation:1,ownerCanvasId:owner(original.ownerCanvasId),data:remapCopyData(original,registry,elementIds,canvasIds,document)};
   if(original.structure==='connection'){
diff --git a/src/lib/canvas-runtime/imports.ts b/src/lib/canvas-runtime/imports.ts
index cab624c..b8b610c 100644
--- a/src/lib/canvas-runtime/imports.ts
+++ b/src/lib/canvas-runtime/imports.ts
@@ -10,7 +10,7 @@ export type ImportUnit = { readonly key: string; readonly dependencies: readonly
 export type ImportLocator = { readonly key: string; readonly cursor: number; readonly nextCursor: number; readonly dependencies: readonly string[]; readonly digest: string; readonly byteLength: number; readonly changeCount: number };
 export type ImportFailure = { readonly key: string; readonly cursor: number; readonly code: string; readonly dependencies?: readonly string[] };
 export type LoadingImportAdmission={readonly version:1;readonly sourceToken:string;readonly operationSequence:number;readonly requiredCanvasIds:readonly Id[]};
-export type NativeImportSource = { readonly loadingAdmission?:LoadingImportAdmission; readonly kind: 'native-json-array' | 'native-ndjson' | 'duplicate-ndjson' | 'duplicate-snapshot' | 'duplicate-plan'; readonly retirement?:FileRetirement;readonly previousFiles?:readonly PreviousImportFile[];readonly snapshotVersion?:2;readonly plan?:DuplicateCheckpoint; readonly copy?: {readonly sourceRevision:number; readonly roots:readonly Id[]}; readonly integrityVersion?:1;readonly sha256?:string; readonly name?:string; readonly fileId: Id; readonly byteLength: number; readonly targetCanvasId: Id; readonly targetEntry?: {readonly id:Id;readonly incarnation:number} };
+export type NativeImportSource = { readonly loadingAdmission?:LoadingImportAdmission; readonly kind: 'native-document' | 'native-json-array' | 'native-ndjson' | 'duplicate-ndjson' | 'duplicate-snapshot' | 'duplicate-plan'; readonly retirement?:FileRetirement;readonly previousFiles?:readonly PreviousImportFile[];readonly snapshotVersion?:2;readonly plan?:DuplicateCheckpoint; readonly copy?: {readonly sourceRevision:number; readonly roots:readonly Id[]}; readonly integrityVersion?:1;readonly sha256?:string; readonly name?:string; readonly fileId: Id; readonly byteLength: number; readonly targetCanvasId: Id; readonly targetEntry?: {readonly id:Id;readonly incarnation:number} };
 export type ImportBinding = {readonly kind:'element';readonly incarnation:number}|{readonly kind:'canvas';readonly entryElementId?:Id};
 export type ImportJob = {
   readonly version: 1 | 2 | 3; readonly id: Id; readonly projectId: Id; readonly sourceFingerprint: string; readonly parserVersion: number;
@@ -29,7 +29,8 @@ export function validateImportJob(job: ImportJob): void {
   if (job.version !== 1 && job.version !== 2 && job.version !== 3) throw fault('import_interpreter_unavailable');
   createImportJob(job);
   if (!Number.isSafeInteger(job.generation) || job.generation<0 || !Number.isSafeInteger(job.cursor) || job.cursor<0 || typeof job.eof!=='boolean' || !['preparing','paused','running','completed','partial','cancelled'].includes(job.status)) throw fault('invalid_import_job');
-  if(job.source&&(!['native-json-array','native-ndjson','duplicate-ndjson','duplicate-snapshot','duplicate-plan'].includes(job.source.kind)||['duplicate-ndjson','duplicate-plan'].includes(job.source.kind)&&(!job.source.copy||!Number.isSafeInteger(job.source.copy.sourceRevision)||job.source.copy.sourceRevision<0||!Array.isArray(job.source.copy.roots)||!job.source.copy.roots.length||job.source.copy.roots.some(id=>typeof id!=='string'||!id))||job.source.name!==undefined&&(typeof job.source.name!=='string'||job.source.name.length>255)||!job.source.fileId||!job.source.targetCanvasId||!Number.isSafeInteger(job.source.byteLength)||job.source.byteLength<0||job.source.targetEntry&&(!job.source.targetEntry.id||!Number.isSafeInteger(job.source.targetEntry.incarnation)||job.source.targetEntry.incarnation<1)))throw fault('invalid_import_source');
+  if(job.source&&(!['native-document','native-json-array','native-ndjson','duplicate-ndjson','duplicate-snapshot','duplicate-plan'].includes(job.source.kind)||['duplicate-ndjson','duplicate-plan'].includes(job.source.kind)&&(!job.source.copy||!Number.isSafeInteger(job.source.copy.sourceRevision)||job.source.copy.sourceRevision<0||!Array.isArray(job.source.copy.roots)||!job.source.copy.roots.length||job.source.copy.roots.some(id=>typeof id!=='string'||!id))||job.source.name!==undefined&&(typeof job.source.name!=='string'||job.source.name.length>255)||!job.source.fileId||!job.source.targetCanvasId||!Number.isSafeInteger(job.source.byteLength)||job.source.byteLength<0||job.source.targetEntry&&(!job.source.targetEntry.id||!Number.isSafeInteger(job.source.targetEntry.incarnation)||job.source.targetEntry.incarnation<1)))throw fault('invalid_import_source');
+  if(job.source?.kind==='native-document'&&job.parserVersion!==4)throw fault('import_interpreter_unavailable');
   if(job.source?.kind==='native-json-array'&&job.parserVersion!==3)throw fault('import_interpreter_unavailable');
   if(job.source?.loadingAdmission){const proof=job.source.loadingAdmission;if(proof.version!==1||typeof proof.sourceToken!=='string'||!proof.sourceToken||proof.sourceToken.length>256||!Number.isSafeInteger(proof.operationSequence)||proof.operationSequence<0||!Array.isArray(proof.requiredCanvasIds)||!proof.requiredCanvasIds.length||proof.requiredCanvasIds.some(id=>typeof id!=='string'||!id)||new Set(proof.requiredCanvasIds).size!==proof.requiredCanvasIds.length)throw fault('loading_import_interpreter_unavailable');}
   if(job.source){
diff --git a/src/lib/canvas-runtime/recovery-encoding.ts b/src/lib/canvas-runtime/recovery-encoding.ts
index 3467cbc..34cbb49 100644
--- a/src/lib/canvas-runtime/recovery-encoding.ts
+++ b/src/lib/canvas-runtime/recovery-encoding.ts
@@ -52,8 +52,8 @@ export function encodeRecoveryValue(input:unknown):Json {
 }
 
 /** Only codec-owned, validated immutable images qualify for the storage copy fast path. */
-export function sealRecoveryImage(formatVersion:1|2|3|4|5|6|7|8|9|10|11|12|13|14,rootRevision:number,localRevision:number,payload:unknown):RecoveryImage {
-  if(![1,2,3,4,5,6,7,8,9,10,11,12,13,14].includes(formatVersion)||!Number.isSafeInteger(rootRevision)||rootRevision<0||!Number.isSafeInteger(localRevision)||localRevision<0||localRevision>rootRevision)throw fault('corrupt_recovery_image');
+export function sealRecoveryImage(formatVersion:1|2|3|4|5|6|7|8|9|10|11|12|13|14|15,rootRevision:number,localRevision:number,payload:unknown):RecoveryImage {
+  if(![1,2,3,4,5,6,7,8,9,10,11,12,13,14,15].includes(formatVersion)||!Number.isSafeInteger(rootRevision)||rootRevision<0||!Number.isSafeInteger(localRevision)||localRevision<0||localRevision>rootRevision)throw fault('corrupt_recovery_image');
   const image=Object.freeze({formatVersion,rootRevision,localRevision,payload:encodeRecoveryValue(payload)});sealed.add(image);return image;
 }
 export function isSealedRecoveryImage(image:RecoveryImage):boolean{return sealed.has(image);}
diff --git a/src/lib/canvas-runtime/recovery.ts b/src/lib/canvas-runtime/recovery.ts
index cd8759a..9651f8f 100644
--- a/src/lib/canvas-runtime/recovery.ts
+++ b/src/lib/canvas-runtime/recovery.ts
@@ -30,7 +30,7 @@ export function encodeRecovery(snapshot: EngineSnapshot): RecoveryImage {
     operations: [...snapshot.operations],
     runtime: { ...(snapshot.runtime.assetBindings?.size?{assetBindings:[...snapshot.runtime.assetBindings]}:{}), ...(snapshot.runtime.loadingRead?{loadingRead:{document:documentValue(snapshot.runtime.loadingRead.document),versions:[...snapshot.runtime.loadingRead.versions]}}:{}), ...(snapshot.runtime.loading?{loading:snapshot.runtime.loading}:{}), ...(snapshot.runtime.orphanFiles?.size?{orphanFiles:[...snapshot.runtime.orphanFiles]}:{}), imports:[...(snapshot.runtime.imports??[])], recoveries:[...(snapshot.runtime.recoveries??[])], runs: [...snapshot.runtime.runs], resources: [...snapshot.runtime.resources], resourcePins: [...snapshot.runtime.resourcePins], acknowledged: documentValue(snapshot.runtime.acknowledged), versions: [...snapshot.runtime.versions], receipts: [...snapshot.runtime.receipts], conflicts: [...snapshot.runtime.conflicts], ledger: { ...snapshot.runtime.ledger, operations: [...snapshot.runtime.ledger.operations], requests: [...snapshot.runtime.ledger.requests] } },
   };
-  return sealRecoveryImage([...(snapshot.runtime.imports?.values()??[])].some(job=>job.source?.kind==='native-json-array')?14:snapshot.runtime.assetBindings?.size?13:snapshot.runtime.loading?(snapshot.runtime.loading.version===6?12:snapshot.runtime.loading.version===5?11:snapshot.runtime.loading.version===4?10:snapshot.runtime.loading.version===3?9:snapshot.runtime.loading.version===2?8:7):[...snapshot.operations.values()].some(intent=>intent.historyEffect)||[...snapshot.runtime.resources.values()].some(resource=>resource.sizing)?6:snapshot.runtime.orphanFiles?.size?5:[...(snapshot.runtime.imports?.values()??[])].some(job=>job.source?.retirement||job.source?.previousFiles?.length)?4:[...snapshot.runtime.resources.values()].some(resource=>resource.retirement)?3:snapshot.runtime.imports?.size ? 2 : 1,snapshot.rootRevision,snapshot.revision,payload);
+  return sealRecoveryImage([...(snapshot.runtime.imports?.values()??[])].some(job=>job.source?.kind==='native-document')?15:[...(snapshot.runtime.imports?.values()??[])].some(job=>job.source?.kind==='native-json-array')?14:snapshot.runtime.assetBindings?.size?13:snapshot.runtime.loading?(snapshot.runtime.loading.version===6?12:snapshot.runtime.loading.version===5?11:snapshot.runtime.loading.version===4?10:snapshot.runtime.loading.version===3?9:snapshot.runtime.loading.version===2?8:7):[...snapshot.operations.values()].some(intent=>intent.historyEffect)||[...snapshot.runtime.resources.values()].some(resource=>resource.sizing)?6:snapshot.runtime.orphanFiles?.size?5:[...(snapshot.runtime.imports?.values()??[])].some(job=>job.source?.retirement||job.source?.previousFiles?.length)?4:[...snapshot.runtime.resources.values()].some(resource=>resource.retirement)?3:snapshot.runtime.imports?.size ? 2 : 1,snapshot.rootRevision,snapshot.revision,payload);
 }
 type ObjectValue = Record<string, unknown>;
 function object(value: unknown): ObjectValue { if (!value || Array.isArray(value) || typeof value !== 'object') throw fault('corrupt_recovery_image'); return value as ObjectValue; }
@@ -94,7 +94,7 @@ function readHistory(history:ObjectValue,operations:ReadonlyMap<Id,OperationInte
   return Object.freeze({undo:freeze(undo),redo:freeze(redo),entries});
 }
 export function decodeRecovery(image: RecoveryImage, registry: Registry): CoreSnapshot & { readonly rootRevision: number; readonly runtime: RuntimeState } {
-  if (![1,2,3,4,5,6,7,8,9,10,11,12,13,14].includes(image.formatVersion)) throw fault('unsupported_recovery_version');
+  if (![1,2,3,4,5,6,7,8,9,10,11,12,13,14,15].includes(image.formatVersion)) throw fault('unsupported_recovery_version');
   integer(image.rootRevision); integer(image.localRevision);
   if (image.localRevision > image.rootRevision || !validJson(image.payload)) throw fault('corrupt_recovery_image');
   // Own the parsed records; mutating a caller's RecoveryImage must not mutate live state.
@@ -249,7 +249,8 @@ export function decodeRecovery(image: RecoveryImage, registry: Registry): CoreSn
     return freeze({...value as RunRecord,outputEvents:array(raw.outputEvents ?? []) as never});
   });
   const imports=table<ImportJob>(runtime.imports??[],(value,id)=>{const job=value as ImportJob;validateImportJob(job);if(job.id!==id||job.projectId!==document.projectId)throw fault('corrupt_recovery_image');return freeze(job);});
-  const hasJsonArrays=[...imports.values()].some(job=>job.source?.kind==='native-json-array');if(hasJsonArrays&&image.formatVersion!==14||image.formatVersion===14&&!hasJsonArrays)throw fault('unsupported_recovery_version');
+  const hasJsonArrays=[...imports.values()].some(job=>job.source?.kind==='native-json-array');if(hasJsonArrays&&image.formatVersion<14||image.formatVersion===14&&!hasJsonArrays)throw fault('unsupported_recovery_version');
+  const hasDocuments=[...imports.values()].some(job=>job.source?.kind==='native-document');if(hasDocuments&&image.formatVersion!==15||image.formatVersion===15&&!hasDocuments)throw fault('unsupported_recovery_version');
   for(const [id,entry]of importFiles(imports)){if(resources.has(id)||assetBindings.has(id))throw fault('import_file_identity_conflict',[id]);if((entry.file.retirement||imports.get(entry.jobId)?.source?.previousFiles?.length)&&image.formatVersion<4)throw fault('unsupported_recovery_version');}
   const orphanFiles=table<OrphanFile>(runtime.orphanFiles??[],(file,id)=>{validateOrphanFile(file,id);return freeze(file);});
   if(orphanFiles.size&&image.formatVersion<5)throw fault('unsupported_recovery_version');for(const id of orphanFiles.keys())if(resources.has(id)||assetBindings.has(id)||importFiles(imports).has(id))throw fault('local_file_identity_conflict',[id]);
diff --git a/src/lib/canvas-runtime/storage-port.ts b/src/lib/canvas-runtime/storage-port.ts
index e32c064..d3cfa61 100644
--- a/src/lib/canvas-runtime/storage-port.ts
+++ b/src/lib/canvas-runtime/storage-port.ts
@@ -2,7 +2,7 @@ import type { Json } from '../canvas-core/types.ts';
 
 /** Portable durable-store contract. Browser database types belong to the adapter. */
 export type StorageScope = { readonly accountId: string; readonly workspaceId: string; readonly projectId: string };
-export type RecoveryImage = { readonly formatVersion: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14; readonly rootRevision: number; readonly localRevision: number; readonly payload: Json };
+export type RecoveryImage = { readonly formatVersion: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15; readonly rootRevision: number; readonly localRevision: number; readonly payload: Json };
 export type DurableBatch = { readonly image: RecoveryImage; readonly deleteFiles?:readonly string[]; readonly depot?:import('./asset-depot.ts').DepotCut; readonly files?: readonly { readonly id: string; readonly bytes: Blob }[] };
 export type StorageLeader = { readonly scope: StorageScope; readonly fence: number; readonly active: boolean; release(): Promise<void> };
 export type StoredFileInfo={readonly id:string;readonly byteLength:number;readonly mimeType:string};
diff --git a/src/lib/canvas-runtime/storage.ts b/src/lib/canvas-runtime/storage.ts
index 90e7bb0..8cfdc1a 100644
--- a/src/lib/canvas-runtime/storage.ts
+++ b/src/lib/canvas-runtime/storage.ts
@@ -31,7 +31,7 @@ function purgedFileIds(image:RecoveryImage):Set<string>{
  return result;
 }
 function validateImage(image: RecoveryImage) {
-  if (![1,2,3,4,5,6,7,8,9,10,11,12,13,14].includes(image.formatVersion)) throw fault('unsupported_recovery_version');
+  if (![1,2,3,4,5,6,7,8,9,10,11,12,13,14,15].includes(image.formatVersion)) throw fault('unsupported_recovery_version');
   if (!Number.isSafeInteger(image.rootRevision) || image.rootRevision < 0 || !Number.isSafeInteger(image.localRevision) || image.localRevision < 0 || image.localRevision > image.rootRevision || !validJson(image.payload)) throw fault('corrupt_recovery_image');
 }
 const requestValue = <T>(request: IDBRequest<T>) => new Promise<T>((resolve, reject) => { request.onsuccess = () => resolve(request.result); request.onerror = () => reject(request.error); });
diff --git a/tests/headless/browser-storage-cases.mjs b/tests/headless/browser-storage-cases.mjs
index c58f16c..dac2df5 100644
--- a/tests/headless/browser-storage-cases.mjs
+++ b/tests/headless/browser-storage-cases.mjs
@@ -757,7 +757,7 @@ export async function run() {
     await storage.commit(leader, { image: image(1) });
     await rejects(() => storage.commit(leader, { image: { ...image(1), payload: null } }), 'storage_revision_conflict');
     await rejects(() => storage.commit(leader, { image: image(3) }), 'storage_revision_gap');
-    await rejects(() => storage.commit(leader, { image: { ...image(2), formatVersion: 15 } }), 'unsupported_recovery_version');
+    await rejects(() => storage.commit(leader, { image: { ...image(2), formatVersion: 16 } }), 'unsupported_recovery_version');
     results.push('same-cut retry is idempotent; conflicting, skipped and future-format cuts reject');
 
     // The first put succeeds before a later duplicate resource aborts the whole transaction.
diff --git a/tests/headless/import-document.test.mjs b/tests/headless/import-document.test.mjs
index aa8f4df..c7959cd 100644
--- a/tests/headless/import-document.test.mjs
+++ b/tests/headless/import-document.test.mjs
@@ -4,3 +4,7 @@ const open=bytes=>openDocumentImportSource({bytes,fingerprint:'original-file',si
 test('export envelope retains nested canvas records, emits root alias and seeks payloads by stable ordinal',async()=>{const reader=await open(source(document));assert.equal(reader.parserVersion,4);const a=await reader.read(0,signal()),b=await reader.read(1,signal());assert.equal(a.value.kind,'canvas');assert.equal(a.value.record.id,'child');assert.equal(a.value.sourceRootId,'root');assert.deepEqual(b.value.record,document.elements[0]);const reopened=await open(source(document));assert.deepEqual(await reopened.read(2,signal()),await reader.read(2,signal()));assert.equal(await reader.read(3,signal()),null);});
 test('envelope fields may be reordered, while future versions, duplicate keys and broken topology reject',async()=>{const reordered={elements:document.elements,tombstones:{},canvases:document.canvases,projectId:'source',documentFormatVersion:1};assert.equal((await(await open(source(reordered))).read(1,signal())).value.record.id,'frame');for(const bad of [{...document,documentFormatVersion:2},{...document,canvases:[...document.canvases,{id:'other',parent:null}]},{...document,canvases:[{id:'root',parent:null},{id:'child',parent:{canvasId:'missing',entryElementId:'e'}}]},{...document,tombstones:{x:0}},'{"documentFormatVersion":1,"documentFormatVersion":1}'])await assert.rejects(open(source(bad)));});
 test('payload errors are per record and large records are never decoded; malformed envelope tails reject',async()=>{const reader=await open(source({...document,elements:[{id:'huge',text:'x'.repeat(300000)},document.elements[1]]}));assert.equal((await reader.read(1,signal())).error,'record_too_large');assert.equal((await reader.read(2,signal())).value.record.id,'inside');await assert.rejects(open(source(JSON.stringify(document)+'garbage')));const controller=new AbortController();controller.abort();await assert.rejects(openDocumentImportSource({bytes:source(document),fingerprint:'x',signal:controller.signal}),/import_aborted/);});
+import {prepareNativeImport} from '../../src/lib/canvas-runtime/import-native.ts';
+import {createImportJob} from '../../src/lib/canvas-runtime/imports.ts';
+import {createRegistry,createDocument} from '../../src/lib/canvas-core/index.ts';
+test('document root aliases also remap component-declared canvas references without reserving a duplicate root',()=>{const registry=createRegistry([{id:'ref',dataVersion:1,structure:'node',features:[],validate:()=>true,copy:{references:[{path:['canvasRef'],target:'canvas',external:'reject'}],omit:[]}}]),target=createDocument('p',[{id:'target',parent:null}],[]),job=createImportJob({id:'job',projectId:'p',parserVersion:4,sourceFingerprint:'file',source:{kind:'native-document',fileId:'file',byteLength:100,targetCanvasId:'target'}}),reserved=[],record={id:'a',incarnation:1,ownerCanvasId:'source',componentId:'ref',dataVersion:1,structure:'node',geometry:{x:0,y:0,width:10,height:10,rotation:0},data:{canvasRef:'source'}},unit=prepareNativeImport({cursor:0,nextCursor:1,key:'record:0',value:{kind:'element',key:'a',record,sourceRootId:'source'}},job,key=>{reserved.push(key);return'new-'+key;},target,registry);assert.equal(unit.changes[0].after.data.canvasRef,'target');assert.equal(unit.changes[0].after.ownerCanvasId,'target');assert.ok(!reserved.includes('canvas:source'));});
diff --git a/tests/headless/imports-engine.test.mjs b/tests/headless/imports-engine.test.mjs
index 5f987b9..8f41855 100644
--- a/tests/headless/imports-engine.test.mjs
+++ b/tests/headless/imports-engine.test.mjs
@@ -291,5 +291,9 @@ test('source read handles verify bound bytes and never publish a result after pr
  }finally{gate.resolve();await engine.close();}
 });
 
-test('JSON array import persists original bytes and byte cursor, resumes after reopen, and preserves edits without duplicating IDs',async()=>{const f=fixture();let engine=await f.open();try{const bytes=new Blob([JSON.stringify([node('json-one'),node('json-two'),node('json-three')])]),id=engine.imports.startJsonArray(bytes,'canvas');await until(engine,s=>s.runtime.imports.get(id).committedSourceKeys.length===1);await engine.imports.pause(id);await engine.settle();const job=engine.imports.getJobs().get(id),first=job.stableIds['element:json-one'];assert.equal(job.parserVersion,3);assert.equal(job.source.kind,'native-json-array');assert.ok(job.cursor>0);assert.equal(f.image().formatVersion,14);decodeRecovery(f.image(),registry);assert.throws(()=>decodeRecovery({...f.image(),formatVersion:13},registry),/unsupported_recovery_version/);assert.throws(()=>decodeRecovery({...f.image(),formatVersion:15},registry),/unsupported_recovery_version/);engine.editor.dispatch({type:'element.data',target:{id:first,incarnation:1},patch:{title:'preserved edit'}});await engine.settle();await engine.close();engine=await f.open();await engine.imports.resume(id);await engine.settle();assert.equal(engine.imports.getJobs().get(id).status,'completed');assert.equal(engine.getSnapshot().document.elements.size,3);assert.equal(engine.getSnapshot().document.elements.get(first).data.title,'preserved edit');assert.equal(f.server().elements.size,3);assert.equal(f.errors.length,0);}finally{await engine.close();}});
+test('JSON array import persists original bytes and byte cursor, resumes after reopen, and preserves edits without duplicating IDs',async()=>{const f=fixture();let engine=await f.open();try{const bytes=new Blob([JSON.stringify([node('json-one'),node('json-two'),node('json-three')])]),id=engine.imports.startJsonArray(bytes,'canvas');await until(engine,s=>s.runtime.imports.get(id).committedSourceKeys.length===1);await engine.imports.pause(id);await engine.settle();const job=engine.imports.getJobs().get(id),first=job.stableIds['element:json-one'];assert.equal(job.parserVersion,3);assert.equal(job.source.kind,'native-json-array');assert.ok(job.cursor>0);assert.equal(f.image().formatVersion,14);decodeRecovery(f.image(),registry);assert.throws(()=>decodeRecovery({...f.image(),formatVersion:13},registry),/unsupported_recovery_version/);assert.throws(()=>decodeRecovery({...f.image(),formatVersion:16},registry),/unsupported_recovery_version/);engine.editor.dispatch({type:'element.data',target:{id:first,incarnation:1},patch:{title:'preserved edit'}});await engine.settle();await engine.close();engine=await f.open();await engine.imports.resume(id);await engine.settle();assert.equal(engine.imports.getJobs().get(id).status,'completed');assert.equal(engine.getSnapshot().document.elements.size,3);assert.equal(engine.getSnapshot().document.elements.get(first).data.title,'preserved edit');assert.equal(f.server().elements.size,3);assert.equal(f.errors.length,0);}finally{await engine.close();}});
 test('JSON array malformed tail keeps its visible prefix and an explicit failure while backend waits',async()=>{const f=fixture(),engine=await f.open(),gate=deferred();f.gate=gate;try{const id=engine.imports.startJsonArray(new Blob(['['+JSON.stringify(node('json-first'))+','+JSON.stringify(node('json-bad'))+',]']),'canvas');await until(engine,s=>s.runtime.imports.get(id).status==='partial');const job=engine.imports.getJobs().get(id);assert.equal(job.committedSourceKeys.length,1);assert.equal(job.failures.at(-1).code,'invalid_json_array');assert.equal(engine.getSnapshot().document.elements.size,1);assert.equal(f.server().elements.size,0);gate.resolve();await engine.settle();assert.equal(f.server().elements.size,1);decodeRecovery(f.image(),registry);}finally{gate.resolve();await engine.close();}});
+
+test('exported document imports into a chosen root with fresh IDs, child ownership and upper connections then reopens',async()=>{const f=fixture();let engine=await f.open();try{const frame={...node('frame').record,componentId:'frame',ownerCanvasId:'source-root'},child={...node('child').record,ownerCanvasId:'source-child'},outside={...node('outside').record,ownerCanvasId:'source-root'},edge={id:'incoming',incarnation:1,ownerCanvasId:'source-root',componentId:'connection',dataVersion:1,structure:'connection',source:{elementId:'outside'},target:{elementId:'frame'},data:{},path:null},input={documentFormatVersion:1,projectId:'source-root',canvases:[{id:'source-root',parent:null},{id:'source-child',parent:{canvasId:'source-root',entryElementId:'frame'}}],elements:[frame,child,outside,edge],tombstones:{old:2}},id=engine.imports.startDocument(new Blob([JSON.stringify(input)]),'canvas');await engine.settle();const job=engine.imports.getJobs().get(id);assert.equal(job.status,'completed',JSON.stringify(job.failures));const doc=engine.getSnapshot().document,frameId=job.stableIds['element:frame'],childId=job.stableIds['canvas:source-child'];assert.equal(doc.canvases.size,2);assert.equal(doc.canvases.get(childId).parent.entryElementId,frameId);assert.equal(doc.elements.get(job.stableIds['element:child']).ownerCanvasId,childId);assert.equal(doc.elements.get(job.stableIds['element:incoming']).ownerCanvasId,'canvas');assert.equal(doc.elements.get(job.stableIds['element:incoming']).target.elementId,frameId);assert.equal(doc.tombstones.has('old'),false);assert.equal(f.image().formatVersion,15);decodeRecovery(f.image(),registry);await engine.close();engine=await f.open();await engine.settle();assert.equal(engine.getSnapshot().document.elements.size,4);assert.equal(engine.imports.getJobs().get(id).status,'completed');assert.equal(f.errors.length,0);}finally{await engine.close();}});
+test('document resource references report an authorization failure while independent text imports',async()=>{const f=fixture(),engine=await f.open();try{const image={...node('image').record,componentId:'image',ownerCanvasId:'source',data:{title:'image',assetId:'untrusted',src:'https://assets.test/untrusted'}},text={...node('text').record,ownerCanvasId:'source'},input={documentFormatVersion:1,projectId:'source',canvases:[{id:'source',parent:null}],elements:[image,text],tombstones:{}},id=engine.imports.startDocument(new Blob([JSON.stringify(input)]),'canvas');await engine.settle();const job=engine.imports.getJobs().get(id);assert.equal(job.status,'partial');assert.ok(job.failures.some(row=>row.code==='import_resource_authorization_required'));assert.equal(engine.getSnapshot().document.elements.size,1);assert.equal(f.server().elements.size,1);}finally{await engine.close();}});
+test('paused exported document resumes ordinal progress after reopen without overwriting an edited prefix',async()=>{const f=fixture();let engine=await f.open();try{const input={documentFormatVersion:1,projectId:'source',canvases:[{id:'source',parent:null}],elements:['d-one','d-two','d-three'].map(id=>({...node(id).record,ownerCanvasId:'source'})),tombstones:{}},id=engine.imports.startDocument(new Blob([JSON.stringify(input)]),'canvas');await until(engine,s=>s.runtime.imports.get(id).committedSourceKeys.length===1);await engine.imports.pause(id);await engine.settle();const job=engine.imports.getJobs().get(id),first=job.stableIds['element:d-one'];assert.equal(job.cursor,1);engine.editor.dispatch({type:'element.data',target:{id:first,incarnation:1},patch:{title:'local edit'}});await engine.settle();await engine.close();engine=await f.open();assert.equal(engine.imports.getJobs().get(id).status,'paused');await engine.imports.resume(id);await engine.settle();assert.equal(engine.imports.getJobs().get(id).status,'completed');assert.equal(engine.getSnapshot().document.elements.size,3);assert.equal(engine.getSnapshot().document.elements.get(first).data.title,'local edit');assert.equal(f.errors.length,0);}finally{await engine.close();}});
diff --git a/tests/headless/recovery-encoding.test.mjs b/tests/headless/recovery-encoding.test.mjs
index 932ec4d..284fb93 100644
--- a/tests/headless/recovery-encoding.test.mjs
+++ b/tests/headless/recovery-encoding.test.mjs
@@ -24,5 +24,5 @@ test('cached subtree height cannot bypass the depth bound and omitted object fie
  const cycle={};cycle.self=cycle;assert.throws(()=>encodeRecoveryValue(cycle),/invalid_recovery_payload/);assert.throws(()=>encodeRecoveryValue({big:1n}));
 });
 test('only factory-owned images are recognized; immutable-looking impostors retain defensive-copy handling',()=>{
- const mutable={title:'before'},image=sealRecoveryImage(2,3,2,{mutable});assert.equal(isSealedRecoveryImage(image),true);assert.equal(isSealedRecoveryImage(structuredClone(image)),false);assert.equal(isSealedRecoveryImage(Object.freeze({...image})),false);mutable.title='after';assert.equal(image.payload.mutable.title,'before');assert.ok(Object.isFrozen(image.payload.mutable));assert.throws(()=>sealRecoveryImage(2,1,2,{}),/corrupt_recovery_image/);assert.equal(isSealedRecoveryImage(sealRecoveryImage(3,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(4,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(5,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(6,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(7,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(8,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(9,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(10,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(11,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(12,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(13,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(14,1,1,{})),true);assert.throws(()=>sealRecoveryImage(15,1,1,{}),/corrupt_recovery_image/);
+ const mutable={title:'before'},image=sealRecoveryImage(2,3,2,{mutable});assert.equal(isSealedRecoveryImage(image),true);assert.equal(isSealedRecoveryImage(structuredClone(image)),false);assert.equal(isSealedRecoveryImage(Object.freeze({...image})),false);mutable.title='after';assert.equal(image.payload.mutable.title,'before');assert.ok(Object.isFrozen(image.payload.mutable));assert.throws(()=>sealRecoveryImage(2,1,2,{}),/corrupt_recovery_image/);assert.equal(isSealedRecoveryImage(sealRecoveryImage(3,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(4,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(5,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(6,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(7,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(8,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(9,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(10,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(11,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(12,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(13,1,1,{})),true);assert.equal(isSealedRecoveryImage(sealRecoveryImage(14,1,1,{})),true);assert.throws(()=>sealRecoveryImage(16,1,1,{}),/corrupt_recovery_image/);
 });
diff --git a/tests/headless/renderer.integration.mjs b/tests/headless/renderer.integration.mjs
index 232b444..efba575 100644
--- a/tests/headless/renderer.integration.mjs
+++ b/tests/headless/renderer.integration.mjs
@@ -415,6 +415,13 @@ try {
   for(let i=0;i<200&&![...documents.get(other).elements.values()].some(e=>e.data.title==='JSON array UI');i++)await pause(20);assert.ok([...documents.get(other).elements.values()].some(e=>e.data.title==='JSON array UI'));
   await call('Page.reload');await until(`[...document.querySelectorAll('[data-headless-canvas] textarea')].some(input=>input.value==='JSON array UI text')&&document.querySelector('[aria-label="画布导入"]').textContent.includes('records.json')`,'JSON array task/content did not recover after reload');
   console.log('PASS JSON array file picker imports and synchronizes native records then recovers its original task and content after reload');
+  await evaluate(`(()=>{const original=HTMLAnchorElement.prototype.click;HTMLAnchorElement.prototype.click=function(){if(this.download){window.__exportedDocument=fetch(this.href).then(response=>response.text());return;}return original.call(this);};document.querySelector('[aria-label="导出图谱"]').click();HTMLAnchorElement.prototype.click=original;})()`);
+  const exported=await evaluate('window.__exportedDocument');assert.equal(JSON.parse(exported).documentFormatVersion,1);const beforeDocumentImport=documents.get(other).elements.size;
+  await evaluate(`(()=>{const transfer=new DataTransfer();transfer.items.add(new File([${JSON.stringify(exported)}],'round-trip.json',{type:'application/json'}));const input=document.querySelector('input[data-canvas-import]');input.files=transfer.files;input.dispatchEvent(new Event('change',{bubbles:true}));})()`);
+  await until(`document.querySelector('[aria-label="画布导入"]')?.textContent.includes('round-trip.json')&&[...document.querySelectorAll('[data-headless-canvas] textarea')].filter(input=>input.value==='JSON array UI text').length===2`,'exported document did not reimport');
+  for(let i=0;i<200&&documents.get(other).elements.size!==beforeDocumentImport+1;i++)await pause(20);assert.equal(documents.get(other).elements.size,beforeDocumentImport+1);await call('Page.reload');await until(`document.querySelector('[aria-label="画布导入"]')?.textContent.includes('round-trip.json')&&[...document.querySelectorAll('[data-headless-canvas] textarea')].filter(input=>input.value==='JSON array UI text').length===2`,'document round trip task/content did not recover');
+  console.log('PASS actual toolbar JSON export reimports through file picker with fresh elements and recovers after reload');
+
 
   await click('账户和工作空间');await until(`!!document.querySelector('#workspace-account:popover-open')`,'account menu did not open');await evaluate(`[...document.querySelectorAll('button')].find(button=>button.textContent.trim()==='退出登录').click()`);
   await until(`location.pathname==='/login'&&!document.body.innerText.includes('This page couldn’t load')`,'logout did not safely detach the view');