diff --git a/apps/web/src/components/chat/queuedMessageEdit.test.ts b/apps/web/src/components/chat/queuedMessageEdit.test.ts
index f7aed151f2fcc..c22b3983c8a6a 100644
--- a/apps/web/src/components/chat/queuedMessageEdit.test.ts
+++ b/apps/web/src/components/chat/queuedMessageEdit.test.ts
@@ -1,5 +1,6 @@
 import { EnvironmentId, ThreadId } from "@t3tools/contracts";
 import { scopeThreadRef } from "@t3tools/client-runtime/environment";
+import { threadContextRecord } from "@t3tools/shared/composerContextReferences";
 import { beforeEach, describe, expect, it } from "vite-plus/test";
 import {
   DraftId,
@@ -86,6 +87,18 @@ describe("queued message file edits", () => {
     expect(store.getComposerDraft(editTarget)).toBeNull();
   });
 
+  it("removes a kept edit draft that held a thread mention", () => {
+    const store = useComposerDraftStore.getState();
+    store.setPrompt(editTarget, "Edited message");
+    store.setThreadContexts(editTarget, [
+      threadContextRecord(scopeThreadRef(environmentId, ThreadId.make("thread:other")), "Other"),
+    ]);
+    expect(
+      recoverQueuedMessageEdit({ editTarget, threadTarget, originalText: "Original message" }),
+    ).toBe("kept");
+    expect(store.getComposerDraft(editTarget)).toBeNull();
+  });
+
   it("reports a removed queued attachment as an edit when the run leaves", () => {
     const store = useComposerDraftStore.getState();
     store.setPrompt(editTarget, "Original message");
diff --git a/apps/web/src/components/chat/queuedMessageEdit.ts b/apps/web/src/components/chat/queuedMessageEdit.ts
index 40a222a9f383a..ee7d954d3b4a4 100644
--- a/apps/web/src/components/chat/queuedMessageEdit.ts
+++ b/apps/web/src/components/chat/queuedMessageEdit.ts
@@ -28,9 +28,8 @@ export function recoverQueuedMessageEdit(input: {
   });
   if (recovery === "kept") {
     store.moveComposerPromptAndImages(input.editTarget, input.threadTarget);
-  } else {
-    store.clearComposerContent(input.editTarget);
   }
+  store.clearComposerContent(input.editTarget);
   return recovery;
 }
 
diff --git a/apps/web/src/components/chat/useQueuedRunEdit.browser.test.tsx b/apps/web/src/components/chat/useQueuedRunEdit.browser.test.tsx
index 4a58d25e48757..0320dd6d6bb18 100644
--- a/apps/web/src/components/chat/useQueuedRunEdit.browser.test.tsx
+++ b/apps/web/src/components/chat/useQueuedRunEdit.browser.test.tsx
@@ -9,11 +9,20 @@ import {
 } from "@t3tools/contracts";
 import { useImperativeHandle, type RefObject } from "react";
 import { describe, expect, it, vi } from "vite-plus/test";
-import { ATTACHMENT_ONLY_BOOTSTRAP_PROMPT } from "@t3tools/shared/composerContextReferences";
+import {
+  ATTACHMENT_ONLY_BOOTSTRAP_PROMPT,
+  threadContextRecord,
+} from "@t3tools/shared/composerContextReferences";
 import { toastManager } from "../ui/toast";
 
 import { act, render } from "../../../test/render";
 import { useComposerDraftStore, useComposerThreadDraft } from "../../composerDraftStore";
+import { formatInlineContextReference } from "../../lib/composerContextReferences";
+import {
+  environmentContextRecord,
+  environmentContextReference,
+  threadContextReference,
+} from "../../lib/composerContextRecords";
 import { deriveComposerSendState } from "../ChatView.logic";
 import { ComposerPrimaryActions } from "./ComposerPrimaryActions";
 import { AppAtomRegistryProvider, appAtomRegistry } from "../../rpc/atomRegistry";
@@ -74,8 +83,8 @@ const RUN = RunId.make("run-1");
 
 type HookResult = ReturnType<typeof useQueuedRunEdit>;
 
-function projection(runs: ReadonlyArray<RunStatus>) {
-  return { runs, messages: [] } as unknown as ThreadStructure;
+function projection(runs: ReadonlyArray<RunStatus>, messages: ReadonlyArray<unknown>) {
+  return { runs, messages } as unknown as ThreadStructure;
 }
 
 function setRuns(ref: ScopedThreadRef, status: string) {
@@ -86,13 +95,14 @@ function Harness(props: {
   readonly threadRef: ScopedThreadRef;
   readonly runStatus: string;
   readonly hookRef: RefObject<HookResult | null>;
+  readonly messages: ReadonlyArray<unknown>;
 }) {
   const result = useQueuedRunEdit({
     environmentId: ENV,
     routeThreadRef: props.threadRef,
     threadDraftTarget: props.threadRef,
     activeThreadId: props.threadRef.threadId,
-    serverProjection: projection([{ id: RUN, status: props.runStatus }]),
+    serverProjection: projection([{ id: RUN, status: props.runStatus }], props.messages),
     promptRef: { current: "" },
     composerRef: { current: null },
   });
@@ -124,10 +134,15 @@ function Harness(props: {
   ) : null;
 }
 
-function view(threadRef: ScopedThreadRef, runStatus: string, hook: { current: HookResult | null }) {
+function view(
+  threadRef: ScopedThreadRef,
+  runStatus: string,
+  hook: { current: HookResult | null },
+  messages: ReadonlyArray<unknown> = [],
+) {
   return (
     <AppAtomRegistryProvider>
-      <Harness threadRef={threadRef} runStatus={runStatus} hookRef={hook} />
+      <Harness threadRef={threadRef} runStatus={runStatus} hookRef={hook} messages={messages} />
     </AppAtomRegistryProvider>
   );
 }
@@ -262,6 +277,56 @@ describe("useQueuedRunEdit", () => {
     );
   });
 
+  it("opens an edit with only the thread and machine records its text still mentions", async () => {
+    const { hook } = setup();
+    const thread = threadContextRecord(THREAD_B, "Support Any File Uploads");
+    const machine = environmentContextRecord(ENV, "Build box");
+    const unreferenced = threadContextRecord(THREAD_A, "Removed earlier");
+    const messageId = MessageId.make("message-1");
+    const text = `wait for ${formatInlineContextReference(threadContextReference(thread))} on ${formatInlineContextReference(environmentContextReference(machine))}`;
+    const messages = [
+      { id: messageId, text, context: { version: 1, records: [thread, machine, unreferenced] } },
+    ];
+    await using _screen = await render(view(THREAD_A, "queued", hook, messages));
+
+    await act(() => requireHook(hook).beginEdit({ runId: RUN, messageId, text, attachments: [] }));
+
+    const draft = useComposerDraftStore.getState().getComposerDraft(requireHook(hook).draftTarget);
+    expect(draft?.prompt).toBe(text);
+    expect(draft?.threadContexts).toEqual([thread]);
+    expect(draft?.environmentContexts).toEqual([machine]);
+  });
+
+  it("saves only the thread mentions still in the edited message", async () => {
+    const { hook } = setup();
+    mocks.editQueuedRun.mockResolvedValue({ _tag: "Success" });
+    const kept = threadContextRecord(THREAD_B, "Kept");
+    const removed = threadContextRecord(THREAD_A, "Removed");
+    const messageId = MessageId.make("message-1");
+    const text = [kept, removed]
+      .map((record) => formatInlineContextReference(threadContextReference(record)))
+      .join(" and ");
+    const messages = [{ id: messageId, text, context: { version: 1, records: [kept, removed] } }];
+    await using _screen = await render(view(THREAD_A, "queued", hook, messages));
+    await act(() => requireHook(hook).beginEdit({ runId: RUN, messageId, text, attachments: [] }));
+    const target = requireHook(hook).draftTarget;
+    await act(() => useComposerDraftStore.getState().setThreadContexts(target, [kept]));
+
+    const draft = useComposerDraftStore.getState().getComposerDraft(target);
+    await requireHook(hook).saveEdit(
+      { ...savedContent(draft?.prompt ?? ""), threadContexts: draft?.threadContexts ?? [] },
+      () => {},
+    );
+
+    expect(mocks.editQueuedRun).toHaveBeenCalledWith(
+      expect.objectContaining({
+        input: expect.objectContaining({
+          edit: expect.objectContaining({ context: { version: 1, records: [kept] } }),
+        }),
+      }),
+    );
+  });
+
   it("keeps an open edit when the user leaves the thread and comes back", async () => {
     const { hook } = setup();
     await using screen = await render(view(THREAD_A, "queued", hook));
diff --git a/apps/web/src/components/chat/useQueuedRunEdit.ts b/apps/web/src/components/chat/useQueuedRunEdit.ts
index 8feb302dc6aae..f8f968487fc75 100644
--- a/apps/web/src/components/chat/useQueuedRunEdit.ts
+++ b/apps/web/src/components/chat/useQueuedRunEdit.ts
@@ -7,6 +7,7 @@ import type { ThreadStructure } from "@t3tools/client-runtime/state/shell";
 import {
   PROVIDER_SEND_TURN_MAX_ATTACHMENTS,
   type ChatAttachment,
+  type ComposerContextRecord,
   type EnvironmentContextRecord,
   type EnvironmentId,
   type MessageId,
@@ -40,6 +41,7 @@ import {
   startAttachmentUpload,
 } from "../../lib/attachmentUploadQueue";
 import { buildMessageContext } from "../../lib/composerContextRecords";
+import { collectInlineContextIds } from "../../lib/composerContextReferences";
 import { readFileAsDataUrl } from "../../lib/imageCompression";
 import type { TerminalContextDraft } from "../../lib/terminalContext";
 import type { ReviewCommentContext } from "../../reviewCommentContext";
@@ -85,6 +87,9 @@ interface QueuedRunEditContent {
   readonly environmentContexts: ReadonlyArray<EnvironmentContextRecord>;
 }
 
+const isDraftOwnedRecord = (record: ComposerContextRecord) =>
+  record.kind === "thread" || record.kind === "environment";
+
 function queuedEditDraftTarget(routeThreadRef: ScopedThreadRef, runId: RunId) {
   return DraftId.make(`queued-edit:${scopedThreadKey(routeThreadRef)}:${runId}`);
 }
@@ -127,10 +132,12 @@ async function submitQueuedRunEdit(input: {
       readImage: readFileAsDataUrl,
       uploadFiles,
     });
+    // The edit draft owns thread and machine mentions, so a chip removed while editing is dropped.
     const keptRecords = (editing.context?.records ?? []).filter(
       (record) =>
-        !("attachmentId" in record) ||
-        editing.existingAttachments.some((attachment) => attachment.id === record.attachmentId),
+        !isDraftOwnedRecord(record) &&
+        (!("attachmentId" in record) ||
+          editing.existingAttachments.some((attachment) => attachment.id === record.attachmentId)),
     );
     const newRecords =
       buildMessageContext({
@@ -233,9 +240,22 @@ export function useQueuedRunEdit(input: {
     if (editing !== null && editing.runId !== request.runId) clearEditDraft(editing.runId);
     const target = queuedEditDraftTarget(routeThreadRef, request.runId);
     const text = stripAttachmentOnlyBootstrapPrompt(request.text);
+    const context = serverProjection?.messages.find(
+      (message) => message.id === request.messageId,
+    )?.context;
+    const referenced = new Set(collectInlineContextIds(text));
+    const records = (context?.records ?? []).filter((record) => referenced.has(record.contextId));
     const store = useComposerDraftStore.getState();
     store.clearComposerContent(target);
     store.setPrompt(target, text);
+    store.setThreadContexts(
+      target,
+      records.filter((record): record is ThreadContextRecord => record.kind === "thread"),
+    );
+    store.setEnvironmentContexts(
+      target,
+      records.filter((record): record is EnvironmentContextRecord => record.kind === "environment"),
+    );
     const threadRef = { environmentId, threadId: activeThreadId };
     queuedRunEdits.begin(
       editKey,
@@ -245,8 +265,7 @@ export function useQueuedRunEdit(input: {
         messageId: request.messageId,
         originalText: text,
         existingAttachments: request.attachments,
-        context: serverProjection?.messages.find((message) => message.id === request.messageId)
-          ?.context,
+        context,
       },
       {
         runs: makeQueuedRunsAtom({