diff --git a/frontend/src/lib/components/sessions/SessionWrapper.svelte b/frontend/src/lib/components/sessions/SessionWrapper.svelte
index 63d2b5594f..bd9dcfb075 100644
--- a/frontend/src/lib/components/sessions/SessionWrapper.svelte
+++ b/frontend/src/lib/components/sessions/SessionWrapper.svelte
@@ -567,13 +567,26 @@
 				}
 				return
 			}
+			let relisted: Awaited<ReturnType<typeof listMoveItems>> | undefined
 			const res = await moveSessionToFork(session.id, req.parent, req.target, {
 				items: req.items.map(({ kind, path }) => ({ kind, path })),
 				removeFromParent: moveRemoveFromParent,
-				isBusy: () => !canMoveToFork
+				isBusy: () => !canMoveToFork,
+				itemsChanged: async () => {
+					relisted = await listMoveItems(req.parent, req.target)
+					return typeof relisted === 'string' || itemKeys(relisted.items) !== itemKeys(req.items)
+				}
 			})
 			if (!res.ok) {
-				if (!req.open) {
+				if (res.changed && relisted !== undefined) {
+					moveRequest = {
+						...req,
+						...(typeof relisted === 'string' ? {} : relisted),
+						target: res.retry ?? req.target,
+						open: true,
+						error: typeof relisted === 'string' ? relisted : res.error
+					}
+				} else if (!req.open) {
 					sendUserToast(res.error, true)
 					moveRequest = undefined
 				} else {
diff --git a/frontend/src/lib/components/sessions/moveSessionToFork.test.ts b/frontend/src/lib/components/sessions/moveSessionToFork.test.ts
index f044802946..b3e3641c10 100644
--- a/frontend/src/lib/components/sessions/moveSessionToFork.test.ts
+++ b/frontend/src/lib/components/sessions/moveSessionToFork.test.ts
@@ -117,4 +117,23 @@ describe('moveSessionToFork', () => {
 			})
 		}
 	)
+
+	it('stops before transferring when the drafts changed while the fork was created', async () => {
+		vi.mocked(materializeForkOutcome).mockResolvedValue({ id: 'wm-fork-new', created: true })
+		vi.mocked(DraftService.transferDrafts).mockClear()
+		const s = addSession()
+		const res = await moveSessionToFork(
+			s.id,
+			'root_ws',
+			{ kind: 'new', fork: { id: 'wm-fork-new', name: 'new', parent_workspace_id: 'root_ws' } },
+			{ items: [], removeFromParent: false, itemsChanged: async () => true }
+		)
+		expect(res).toMatchObject({
+			ok: false,
+			changed: true,
+			retry: { kind: 'existing', id: 'wm-fork-new', replace: true }
+		})
+		expect(DraftService.transferDrafts).not.toHaveBeenCalled()
+		expect(sessionState.sessions.find((x) => x.id === s.id)?.workspace_id).toBe('root_ws')
+	})
 })
diff --git a/frontend/src/lib/components/sessions/moveSessionToFork.ts b/frontend/src/lib/components/sessions/moveSessionToFork.ts
index 00bde2dd88..9d0c219784 100644
--- a/frontend/src/lib/components/sessions/moveSessionToFork.ts
+++ b/frontend/src/lib/components/sessions/moveSessionToFork.ts
@@ -24,7 +24,14 @@ export type MoveTarget =
 export type MoveSessionResult =
 	| { ok: true; forkId: string; copied: number; removed: number }
 	// `retry` is the target to retry with once the fork exists, so a retry never creates it again.
-	| { ok: false; error: string; conflicts?: DraftItemRef[]; retry?: MoveTarget }
+	// `changed`: the session's drafts are no longer the ones listed, so the caller lists them again.
+	| {
+			ok: false
+			error: string
+			conflicts?: DraftItemRef[]
+			retry?: MoveTarget
+			changed?: boolean
+	  }
 
 /**
  * Send every debounced draft save for `workspace` to the server. Returns an error message
@@ -89,6 +96,8 @@ export async function moveSessionToFork(
 		removeFromParent: boolean
 		// A turn running in the parent keeps writing there while its drafts move away.
 		isBusy?: () => boolean
+		// Saves pending in the parent and tells whether the session's drafts differ from `items`.
+		itemsChanged?: () => Promise<boolean>
 	}
 ): Promise<MoveSessionResult> {
 	const unsaved = await flushPendingSaves(parent)
@@ -103,6 +112,16 @@ export async function moveSessionToFork(
 		fork = { kind: 'existing', id: made.id, replace: made.created }
 		// Creating the fork takes seconds, long enough for a job's auto-resume to start a turn.
 		if (opts.isBusy?.()) return { ok: false, error: busy, retry: fork }
+		// So does an edit in the session's preview: it lands in the parent, possibly as a draft the
+		// list did not have.
+		if (await opts.itemsChanged?.()) {
+			return {
+				ok: false,
+				error: "This session's drafts changed. Check the list and confirm again.",
+				retry: fork,
+				changed: true
+			}
+		}
 	} else {
 		fork = target
 		// An editor open in the fork may hold edits not yet saved. Saved now, they become the