fix(web): reveal folded imported responses when opening citations

apps/web/src/components/chat/MessagesTimeline.browser.test.tsx

@@ -795,6 +795,62 @@ describe("MessagesTimeline attachments", () => {
 });
 
 describe("MessagesTimeline history and thread links", () => {
+  it.each([
+    ["imported runless", null],
+    ["standard", RunId.make("citation-run")],
+  ] as const)("reveals a cited response inside a folded %s turn", async (_label, runId) => {
+    const quote = "The imported response contains this cited detail.";
+    const props = {
+      ...baseProps(),
+      timelineEntries: [
+        message("Investigate the issue.", { runId }, "citation-prompt"),
+        message(quote, { role: "assistant", runId }, "citation-source"),
+        message("Investigation complete.", { role: "assistant", runId }, "citation-answer"),
+      ],
+    };
+    await renderElement(<MessagesTimeline {...props} />);
+    const source = () =>
+      container.querySelector<HTMLElement>('[data-assistant-citation-source="citation-source"]');
+    await vi.waitFor(() => expect(text()).toContain("Investigation complete."));
+    expect(buttons(/^Worked/)).toHaveLength(1);
+    expect(source()).toBeNull();
+
+    await act(async () =>
+      roots.at(-1)!.render(
+        <MessagesTimeline
+          {...props}
+          citationRequest={{
+            key: "open-citation",
+            citation: {
+              version: 1,
+              environmentId: ENVIRONMENT_ID,
+              threadId: ThreadId.make(`thread-${threadCount}`),
+              messageId: MessageId.make("citation-source"),
+              text: quote,
+              start: 0,
+              end: quote.length,
+              prefix: "",
+              suffix: "",
+            },
+          }}
+        />,
+      ),
+    );
+
+    await vi.waitFor(() => {
+      expect(source()?.textContent ?? "").toContain(quote);
+      const highlight = CSS.highlights.get("t3-assistant-citation");
+      expect(highlight).toBeDefined();
+      const range = [...highlight!][0] as Range;
+      expect(range.toString()).toBe(quote);
+      const viewport = container.querySelector<HTMLElement>("[data-assistant-citation-viewport]")!;
+      const bounds = range.getBoundingClientRect();
+      expect(bounds.height).toBeGreaterThan(0);
+      expect(bounds.top).toBeGreaterThanOrEqual(viewport.getBoundingClientRect().top);
+      expect(bounds.bottom).toBeLessThanOrEqual(viewport.getBoundingClientRect().bottom);
+    });
+  });
+
   it("loads earlier turns from a control ahead of the bounded timeline", async () => {
     const onLoadEarlier = vi.fn();
     await renderTimeline([message("Recent activity")], {

apps/web/src/components/chat/MessagesTimeline.tsx

@@ -800,8 +800,7 @@ const ConversationTimeline = memo(function ConversationTimeline({
     });
   }, [latestRun, listIdentityKey]);
 
-  // Find the fold that hides the match: imported turns have no run id but still
-  // fold under a synthetic key, so the match's own run id cannot open them.
+  // Imported turns fold under synthetic keys rather than the entries' own run ids.
   const findFoldRunIds = findActive
     ? timelineTurnFoldRunIdsByEntryId({
         timelineEntries,
@@ -811,9 +810,8 @@ const ConversationTimeline = memo(function ConversationTimeline({
         runlessWorkActive,
       })
     : null;
-  const activeFindRunId = activeFindMatch
-    ? findFoldRunIds?.get(activeFindMatch.entryId)
-    : undefined;
+  const activeFindRunId =
+    findActive && activeFindMatch ? findFoldRunIds?.get(activeFindMatch.entryId) : undefined;
   const [expandedFindRunId, setExpandedFindRunId] = useState<RunId | undefined>();
   if (expandedFindRunId !== activeFindRunId) {
     setExpandedFindRunId(activeFindRunId);
@@ -1003,6 +1001,17 @@ const ConversationTimeline = memo(function ConversationTimeline({
     viewport: timelineViewportElement,
     historyLoading: citationHistoryLoading,
     loadEarlier,
+    getTurnFoldRunId: (entryId) =>
+      (
+        findFoldRunIds ??
+        timelineTurnFoldRunIdsByEntryId({
+          timelineEntries,
+          latestRun,
+          runningRunId,
+          isWorking,
+          runlessWorkActive,
+        })
+      ).get(entryId),
     onExpandTurn: expandCitedRun,
     onManualNavigation,
   });

apps/web/src/components/chat/useAssistantCitationTarget.ts

@@ -20,6 +20,7 @@ export function useAssistantCitationTarget({
   viewport,
   historyLoading,
   loadEarlier,
+  getTurnFoldRunId,
   onExpandTurn,
   onManualNavigation,
 }: {
@@ -30,6 +31,7 @@ export function useAssistantCitationTarget({
   viewport: HTMLElement | null;
   historyLoading: boolean;
   loadEarlier: CitationHistoryPage | null;
+  getTurnFoldRunId: (entryId: string) => RunId | undefined;
   onExpandTurn: (runId: RunId) => void;
   onManualNavigation: () => void;
 }) {
@@ -123,12 +125,14 @@ export function useAssistantCitationTarget({
       (row) => row.kind === "message" && row.message.id === navigation.target.citation.messageId,
     );
     if (index < 0) {
-      if (source.message.runId) onExpandTurn(source.message.runId);
+      const foldRunId = getTurnFoldRunId(source.id);
+      if (foldRunId) onExpandTurn(foldRunId);
       return;
     }
     if (listLoaded && listRef.current) setReady(navigation.target);
   }, [
     entries,
+    getTurnFoldRunId,
     historyLoading,
     listLoaded,
     listRef,