Revert "Add experimental newest-first issue thread" (paperclipai#5460)

This is actually bad. Glad it was under experiments.

Author: devinfoley

packages/shared/src/types/instance.ts

@@ -29,7 +29,6 @@ export interface InstanceGeneralSettings {
 export interface InstanceExperimentalSettings {
   enableEnvironments: boolean;
   enableIsolatedWorkspaces: boolean;
-  enableNewestFirstIssueThread: boolean;
   autoRestartDevServerWhenIdle: boolean;
   enableIssueGraphLivenessAutoRecovery: boolean;
   issueGraphLivenessAutoRecoveryLookbackHours: number;

packages/shared/src/validators/instance.ts

@@ -38,7 +38,6 @@ export const patchInstanceGeneralSettingsSchema = instanceGeneralSettingsSchema.
 export const instanceExperimentalSettingsSchema = z.object({
   enableEnvironments: z.boolean().default(false),
   enableIsolatedWorkspaces: z.boolean().default(false),
-  enableNewestFirstIssueThread: z.boolean().default(false),
   autoRestartDevServerWhenIdle: z.boolean().default(false),
   enableIssueGraphLivenessAutoRecovery: z.boolean().default(false),
   issueGraphLivenessAutoRecoveryLookbackHours: z

server/src/__tests__/instance-settings-routes.test.ts

@@ -64,7 +64,6 @@ describe("instance settings routes", () => {
     mockInstanceSettingsService.getExperimental.mockResolvedValue({
       enableEnvironments: false,
       enableIsolatedWorkspaces: false,
-      enableNewestFirstIssueThread: false,
       autoRestartDevServerWhenIdle: false,
       enableIssueGraphLivenessAutoRecovery: true,
       issueGraphLivenessAutoRecoveryLookbackHours: 24,
@@ -82,7 +81,6 @@ describe("instance settings routes", () => {
       experimental: {
         enableEnvironments: true,
         enableIsolatedWorkspaces: true,
-        enableNewestFirstIssueThread: false,
         autoRestartDevServerWhenIdle: false,
         enableIssueGraphLivenessAutoRecovery: true,
         issueGraphLivenessAutoRecoveryLookbackHours: 24,
@@ -125,7 +123,6 @@ describe("instance settings routes", () => {
     expect(getRes.body).toEqual({
       enableEnvironments: false,
       enableIsolatedWorkspaces: false,
-      enableNewestFirstIssueThread: false,
       autoRestartDevServerWhenIdle: false,
       enableIssueGraphLivenessAutoRecovery: true,
       issueGraphLivenessAutoRecoveryLookbackHours: 24,

server/src/services/instance-settings.ts

@@ -41,7 +41,6 @@ function normalizeExperimentalSettings(raw: unknown): InstanceExperimentalSettin
     return {
       enableEnvironments: parsed.data.enableEnvironments ?? false,
       enableIsolatedWorkspaces: parsed.data.enableIsolatedWorkspaces ?? false,
-      enableNewestFirstIssueThread: parsed.data.enableNewestFirstIssueThread ?? false,
       autoRestartDevServerWhenIdle: parsed.data.autoRestartDevServerWhenIdle ?? false,
       enableIssueGraphLivenessAutoRecovery: parsed.data.enableIssueGraphLivenessAutoRecovery ?? false,
       issueGraphLivenessAutoRecoveryLookbackHours:
@@ -52,7 +51,6 @@ function normalizeExperimentalSettings(raw: unknown): InstanceExperimentalSettin
   return {
     enableEnvironments: false,
     enableIsolatedWorkspaces: false,
-    enableNewestFirstIssueThread: false,
     autoRestartDevServerWhenIdle: false,
     enableIssueGraphLivenessAutoRecovery: false,
     issueGraphLivenessAutoRecoveryLookbackHours:

ui/src/components/IssueChatThread.test.tsx

@@ -295,19 +295,16 @@ function createFileDragEvent(type: string, files: File[]) {
 
 describe("IssueChatThread", () => {
   let container: HTMLDivElement;
-  const originalDocumentElementScrollIntoView = document.documentElement.scrollIntoView;
 
   beforeEach(() => {
     container = document.createElement("div");
     document.body.appendChild(container);
     window.scrollTo = vi.fn();
-    document.documentElement.scrollIntoView = vi.fn() as unknown as typeof document.documentElement.scrollIntoView;
     localStorage.clear();
   });
 
   afterEach(() => {
     container.remove();
-    document.documentElement.scrollIntoView = originalDocumentElementScrollIntoView;
     vi.useRealTimers();
     appendMock.mockReset();
     markdownEditorFocusMock.mockReset();
@@ -330,7 +327,6 @@ describe("IssueChatThread", () => {
             liveRuns={[]}
             onAdd={async () => {}}
             showComposer={false}
-            newestFirst
             enableLiveTranscriptPolling={false}
           />
         </MemoryRouter>,
@@ -340,16 +336,6 @@ describe("IssueChatThread", () => {
     expect(container.textContent).toContain("Jump to latest");
     expect(container.textContent).not.toContain("Chat (");
 
-    const threadRoot = container.querySelector('[data-testid="thread-root"]');
-    const jumpButton = Array.from(container.querySelectorAll("button")).find(
-      (button) => button.textContent === "Jump to latest",
-    );
-    expect(threadRoot).not.toBeNull();
-    expect(jumpButton).toBeDefined();
-    expect(
-      threadRoot?.compareDocumentPosition(jumpButton!),
-    ).toBe(Node.DOCUMENT_POSITION_FOLLOWING);
-
     const viewport = container.querySelector('[data-testid="thread-viewport"]') as HTMLDivElement | null;
     expect(viewport).not.toBeNull();
     expect(viewport?.className).not.toContain("overflow-y-auto");
@@ -360,106 +346,6 @@ describe("IssueChatThread", () => {
     });
   });
 
-  it("defaults to oldest-first rendering and jump placement", () => {
-    const root = createRoot(container);
-
-    act(() => {
-      root.render(
-        <MemoryRouter>
-          <IssueChatThread
-            comments={[
-              {
-                id: "comment-older",
-                companyId: "company-1",
-                issueId: "issue-1",
-                authorAgentId: "agent-1",
-                authorUserId: null,
-                body: "Older comment",
-                authorType: "agent",
-                presentation: null,
-                metadata: null,
-                createdAt: new Date("2026-04-06T12:00:00.000Z"),
-                updatedAt: new Date("2026-04-06T12:00:00.000Z"),
-              },
-              {
-                id: "comment-newer",
-                companyId: "company-1",
-                issueId: "issue-1",
-                authorAgentId: "agent-1",
-                authorUserId: null,
-                body: "Newer comment",
-                authorType: "agent",
-                presentation: null,
-                metadata: null,
-                createdAt: new Date("2026-04-06T12:01:00.000Z"),
-                updatedAt: new Date("2026-04-06T12:01:00.000Z"),
-              },
-            ]}
-            linkedRuns={[]}
-            timelineEvents={[]}
-            liveRuns={[]}
-            onAdd={async () => {}}
-            showComposer={false}
-            enableLiveTranscriptPolling={false}
-          />
-        </MemoryRouter>,
-      );
-    });
-
-    const rows = Array.from(container.querySelectorAll('[data-testid="issue-chat-message-row"]'));
-    expect(rows[0]?.textContent).toContain("Older comment");
-    expect(rows[1]?.textContent).toContain("Newer comment");
-
-    const threadRoot = container.querySelector('[data-testid="thread-root"]');
-    const jumpButton = Array.from(container.querySelectorAll("button")).find(
-      (button) => button.textContent === "Jump to latest",
-    );
-    expect(threadRoot).not.toBeNull();
-    expect(jumpButton).toBeDefined();
-    expect(
-      threadRoot?.compareDocumentPosition(jumpButton!),
-    ).toBe(Node.DOCUMENT_POSITION_PRECEDING);
-
-    act(() => {
-      root.unmount();
-    });
-  });
-
-  it("renders the jump control above the thread when newest-first mode is disabled", () => {
-    const root = createRoot(container);
-
-    act(() => {
-      root.render(
-        <MemoryRouter>
-          <IssueChatThread
-            comments={[]}
-            linkedRuns={[]}
-            timelineEvents={[]}
-            liveRuns={[]}
-            onAdd={async () => {}}
-            showComposer={false}
-            newestFirst={false}
-            enableLiveTranscriptPolling={false}
-          />
-        </MemoryRouter>,
-      );
-    });
-
-    const threadRoot = container.querySelector('[data-testid="thread-root"]');
-    const jumpButton = Array.from(container.querySelectorAll("button")).find(
-      (button) => button.textContent === "Jump to latest",
-    );
-    expect(threadRoot).not.toBeNull();
-    expect(jumpButton).toBeDefined();
-    expect(
-      threadRoot?.compareDocumentPosition(jumpButton!),
-    ).toBe(Node.DOCUMENT_POSITION_PRECEDING);
-
-    act(() => {
-      root.unmount();
-    });
-  });
-
   it("renders the composer in planning mode when the issue is in planning mode", () => {
     const root = createRoot(container);
 
@@ -1073,7 +959,6 @@ describe("IssueChatThread", () => {
           agentMap={issueChatLongThreadAgentMap}
           currentUserId="user-board"
           onAdd={async () => {}}
-          newestFirst
           enableLiveTranscriptPolling={false}
           onRefreshLatestComments={async () => {
             setComments([olderComment, latestComment]);
@@ -1110,15 +995,15 @@ describe("IssueChatThread", () => {
     });
   });
 
-  it("findLatestCommentMessageIndex prefers the first comment-anchored row when newest renders first", () => {
+  it("findLatestCommentMessageIndex prefers the last comment-anchored row (PAP-2672)", () => {
     const messages = [
       { metadata: { custom: { anchorId: "comment-a" } } },
       { metadata: { custom: { anchorId: "run-1" } } },
       { metadata: { custom: { anchorId: "comment-b" } } },
       { metadata: { custom: { anchorId: "run-2" } } },
       { metadata: { custom: { anchorId: "activity-3" } } },
     ];
-    expect(findLatestCommentMessageIndex(messages as never)).toBe(0);
+    expect(findLatestCommentMessageIndex(messages as never)).toBe(2);
     expect(
       findLatestCommentMessageIndex([
         { metadata: { custom: { anchorId: "run-only" } } },
@@ -1127,17 +1012,6 @@ describe("IssueChatThread", () => {
     expect(findLatestCommentMessageIndex([] as never)).toBe(-1);
   });
 
-  it("findLatestCommentMessageIndex prefers the last comment-anchored row when newest-first mode is disabled", () => {
-    const messages = [
-      { metadata: { custom: { anchorId: "comment-a" } } },
-      { metadata: { custom: { anchorId: "run-1" } } },
-      { metadata: { custom: { anchorId: "comment-b" } } },
-      { metadata: { custom: { anchorId: "run-2" } } },
-      { metadata: { custom: { anchorId: "activity-3" } } },
-    ];
-    expect(findLatestCommentMessageIndex(messages as never, false)).toBe(2);
-  });
-
   it("keeps the direct render path for short threads under the virtualization threshold", () => {
     const root = createRoot(container);
     const directComments = issueChatLongThreadComments.slice(0, 12);
@@ -1846,50 +1720,6 @@ describe("IssueChatThread", () => {
     });
   });
 
-  it("renders the comment timestamp above the comment body", () => {
-    vi.useFakeTimers();
-    vi.setSystemTime(new Date("2026-04-08T12:00:00.000Z"));
-    const root = createRoot(container);
-
-    act(() => {
-      root.render(
-        <MemoryRouter>
-          <IssueChatThread
-            comments={[{
-              id: "comment-1",
-              companyId: "company-1",
-              issueId: "issue-1",
-              authorAgentId: "agent-1",
-              authorUserId: null,
-              body: "Agent summary",
-              authorType: "agent",
-              presentation: null,
-              metadata: null,
-              createdAt: new Date("2026-04-06T12:00:00.000Z"),
-              updatedAt: new Date("2026-04-06T12:00:00.000Z"),
-            }]}
-            linkedRuns={[]}
-            timelineEvents={[]}
-            liveRuns={[]}
-            onAdd={async () => {}}
-            showComposer={false}
-            newestFirst
-            enableLiveTranscriptPolling={false}
-          />
-        </MemoryRouter>,
-      );
-    });
-
-    const text = container.textContent ?? "";
-    const timestampIndex = text.indexOf("2d ago");
-    expect(timestampIndex).toBeGreaterThanOrEqual(0);
-    expect(timestampIndex).toBeLessThan(text.indexOf("Agent summary"));
-
-    act(() => {
-      root.unmount();
-    });
-  });
-
   it("shows deferred wake badge only for hold-deferred queued comments", () => {
     const root = createRoot(container);