diff --git a/server/src/__tests__/issue-selected-agent-chat-routes.test.ts b/server/src/__tests__/issue-selected-agent-chat-routes.test.ts
index 21b9b40b648..75e54a91d3a 100644
--- a/server/src/__tests__/issue-selected-agent-chat-routes.test.ts
+++ b/server/src/__tests__/issue-selected-agent-chat-routes.test.ts
@@ -45,6 +45,10 @@ const mockAccessDecide = vi.hoisted(() => vi.fn(async (input: { action?: string
 
 const mockLogActivity = vi.hoisted(() => vi.fn(async () => undefined));
 
+const mockResolveHeartbeatSchedulingSuppression = vi.hoisted(() =>
+  vi.fn((): { suppressed: boolean; reason: string | null } => ({ suppressed: false, reason: null })),
+);
+
 vi.mock("../services/index.js", () => ({
   companyService: () => ({}),
   accessService: () => ({
@@ -98,6 +102,7 @@ vi.mock("../services/index.js", () => ({
   routineService: () => ({
     syncRunStatusForIssue: vi.fn(async () => undefined),
   }),
+  resolveHeartbeatSchedulingSuppression: mockResolveHeartbeatSchedulingSuppression,
   workProductService: () => ({}),
 }));
 
@@ -253,6 +258,25 @@ describe("selected-agent issue chat backend", () => {
       ASSIGNEE_AGENT_ID,
       expect.anything(),
     );
+    expect(res.body.wake).toEqual({ suppressed: false, reason: null });
+  });
+
+  it("reports wake suppression so the chat UI can explain a silent no-reply", async () => {
+    mockResolveHeartbeatSchedulingSuppression.mockReturnValueOnce({
+      suppressed: true,
+      reason: "worktree_instance",
+    });
+    const db = createDbStub(
+      [makeAgent({ id: CEO_AGENT_ID, name: "CEO", role: "ceo" })],
+      [],
+    );
+
+    const res = await request(await createApp(db))
+      .post(`/api/issues/${ISSUE_ID}/selected-agent-chat/comments`)
+      .send({ body: "hello?" });
+
+    expect(res.status, JSON.stringify(res.body)).toBe(201);
+    expect(res.body.wake).toEqual({ suppressed: true, reason: "worktree_instance" });
   });
 
   it("titles new board chat issues from the first selected-agent message and stores the target agent", async () => {
diff --git a/server/src/routes/issues.ts b/server/src/routes/issues.ts
index 5b520dc3bcc..ff6d346a861 100644
--- a/server/src/routes/issues.ts
+++ b/server/src/routes/issues.ts
@@ -98,6 +98,7 @@ import {
   executionWorkspaceService,
   goalService,
   heartbeatService,
+  resolveHeartbeatSchedulingSuppression,
   issueApprovalService,
   issueRecoveryActionService,
   issueThreadInteractionService,
@@ -8920,6 +8921,10 @@ export function issueRoutes(
           agentId: targetAgent.id,
         }, "failed to wake selected-agent chat target on issue comment"));
 
+      // Tell the client whether the wake can actually run here: on worktree
+      // instances scheduling is suppressed, and a silent no-reply chat reads
+      // as "sending did nothing" (PAP-13345).
+      const wakeSuppression = resolveHeartbeatSchedulingSuppression();
       res.status(201).json({
         comment,
         targetAgent: {
@@ -8928,6 +8933,10 @@ export function issueRoutes(
           role: targetAgent.role,
           status: targetAgent.status,
         },
+        wake: {
+          suppressed: wakeSuppression.suppressed,
+          reason: wakeSuppression.reason,
+        },
       });
     },
   );
diff --git a/ui/src/api/issues.ts b/ui/src/api/issues.ts
index 246f7b3bb09..2ecc438111d 100644
--- a/ui/src/api/issues.ts
+++ b/ui/src/api/issues.ts
@@ -41,6 +41,11 @@ export type SelectedAgentChatTarget = {
 export type SelectedAgentChatCommentResponse = {
   comment: IssueComment;
   targetAgent: SelectedAgentChatTarget;
+  /** Whether the target-agent wake could be scheduled for this send. */
+  wake?: {
+    suppressed: boolean;
+    reason: "worktree_instance" | "database_restore_in_progress" | null;
+  };
 };
 
 export type ResolveRecoveryActionResponse = {
diff --git a/ui/src/components/ActivityFeed.tsx b/ui/src/components/ActivityFeed.tsx
index 15cd08cb73e..af486dfbef0 100644
--- a/ui/src/components/ActivityFeed.tsx
+++ b/ui/src/components/ActivityFeed.tsx
@@ -3,6 +3,7 @@ import { useQuery } from "@tanstack/react-query";
 import type { ActivityEvent, Agent } from "@paperclipai/shared";
 import { activityApi } from "../api/activity";
 import { agentsApi } from "../api/agents";
+import { authApi } from "../api/auth";
 import { issuesApi } from "../api/issues";
 import { queryKeys } from "../lib/queryKeys";
 import { useCompany } from "../context/CompanyContext";
@@ -245,11 +246,13 @@ function CollapsedFeedGroup({
   agentMap,
   entityNameMap,
   entityTitleMap,
+  boardChatIssueRefs,
 }: {
   group: CollapsedGroup;
   agentMap: Map<string, Agent>;
   entityNameMap: Map<string, string>;
   entityTitleMap: Map<string, string>;
+  boardChatIssueRefs?: ReadonlyMap<string, string>;
 }) {
   const [expanded, setExpanded] = useState(false);
   const actor = group.latestEvent.actorType === "agent"
@@ -301,6 +304,7 @@ function CollapsedFeedGroup({
               agentMap={agentMap}
               entityNameMap={entityNameMap}
               entityTitleMap={entityTitleMap}
+              boardChatIssueRefs={boardChatIssueRefs}
               isMuted
             />
           ))}
@@ -360,6 +364,27 @@ export function ActivityFeed({ className }: ActivityFeedProps) {
     enabled: !!selectedCompanyId,
   });
 
+  // Conference Room conversations are board_chat issues hidden from the
+  // default list above; fetch them separately so their events resolve to an
+  // identifier and deep-link to the room instead of a broken issue URL.
+  const { data: boardChatIssues } = useQuery({
+    queryKey: [...queryKeys.issues.list(selectedCompanyId ?? ""), "board-chat-refs"],
+    queryFn: () =>
+      issuesApi.list(selectedCompanyId!, {
+        originKind: "board_chat",
+        limit: 100,
+        sortField: "updated",
+        sortDir: "desc",
+      }),
+    enabled: !!selectedCompanyId,
+  });
+
+  const { data: session } = useQuery({
+    queryKey: queryKeys.auth.session,
+    queryFn: () => authApi.getSession(),
+  });
+  const currentUserId = session?.user?.id ?? session?.session?.userId ?? null;
+
   const agentMap = useMemo(() => {
     const map = new Map<string, Agent>();
     for (const a of agents ?? []) map.set(a.id, a);
@@ -370,14 +395,22 @@ export function ActivityFeed({ className }: ActivityFeedProps) {
     const map = new Map<string, string>();
     for (const a of agents ?? []) map.set(`agent:${a.id}`, a.name);
     for (const i of issues ?? []) map.set(`issue:${i.id}`, i.identifier ?? i.id);
+    for (const i of boardChatIssues ?? []) map.set(`issue:${i.id}`, i.identifier ?? i.id);
     return map;
-  }, [agents, issues]);
+  }, [agents, issues, boardChatIssues]);
 
   const entityTitleMap = useMemo(() => {
     const map = new Map<string, string>();
     for (const i of issues ?? []) map.set(`issue:${i.id}`, i.title);
+    for (const i of boardChatIssues ?? []) map.set(`issue:${i.id}`, i.title);
     return map;
-  }, [issues]);
+  }, [issues, boardChatIssues]);
+
+  const boardChatIssueRefs = useMemo(() => {
+    const map = new Map<string, string>();
+    for (const i of boardChatIssues ?? []) map.set(i.id, i.identifier || i.id);
+    return map;
+  }, [boardChatIssues]);
 
   const entityStatusMap = useMemo(() => {
     const map = new Map<string, string>();
@@ -389,6 +422,16 @@ export function ActivityFeed({ className }: ActivityFeedProps) {
   const processedItems = useMemo(() => {
     const events = (activity ?? [])
       .filter((evt) => {
+        // The board user's own chat messages are not agent activity — they
+        // already see them in the thread they just typed into (PAP-13345).
+        if (
+          (evt.action === "issue.commented" || evt.action === "issue.comment_added")
+          && evt.actorType === "user"
+          && currentUserId
+          && evt.actorId === currentUserId
+        ) {
+          return false;
+        }
         const tier = getEventTier(evt);
         if (!showAllActivity && tier === 3) return false;
         return matchesFilter(evt, filter);
@@ -396,7 +439,7 @@ export function ActivityFeed({ className }: ActivityFeedProps) {
       .sort((a, b) => new Date(b.createdAt).getTime() - new Date(a.createdAt).getTime());
 
     return collapseSequential(events);
-  }, [activity, filter, showAllActivity]);
+  }, [activity, filter, showAllActivity, currentUserId]);
 
   const visibleItems = processedItems.slice(0, visibleCount);
   const hasMore = processedItems.length > visibleCount;
@@ -491,6 +534,7 @@ export function ActivityFeed({ className }: ActivityFeedProps) {
               agentMap={agentMap}
               entityNameMap={entityNameMap}
               entityTitleMap={entityTitleMap}
+              boardChatIssueRefs={boardChatIssueRefs}
             />
           </div>
         </div>
@@ -513,6 +557,7 @@ export function ActivityFeed({ className }: ActivityFeedProps) {
               entityNameMap={entityNameMap}
               entityTitleMap={entityTitleMap}
               entityStatusMap={entityStatusMap}
+              boardChatIssueRefs={boardChatIssueRefs}
               isActive={isActiveHeartbeat}
             />
           </div>
@@ -531,6 +576,7 @@ export function ActivityFeed({ className }: ActivityFeedProps) {
             entityNameMap={entityNameMap}
             entityTitleMap={entityTitleMap}
             entityStatusMap={entityStatusMap}
+            boardChatIssueRefs={boardChatIssueRefs}
             isActive={isActiveHeartbeat}
             isMuted
           />
diff --git a/ui/src/components/AssistantChat.tsx b/ui/src/components/AssistantChat.tsx
index c870cc2e8a7..21d2cb4864c 100644
--- a/ui/src/components/AssistantChat.tsx
+++ b/ui/src/components/AssistantChat.tsx
@@ -27,9 +27,15 @@ import {
   SelectValue,
 } from "@/components/ui/select";
 import type { MentionOption } from "./MarkdownEditor";
+import { accessApi } from "../api/access";
 import type { ActiveRunForIssue, LiveRunForIssue } from "../api/heartbeats";
 import { heartbeatsApi } from "../api/heartbeats";
 import { issuesApi } from "../api/issues";
+import {
+  buildCompanyUserLabelMap,
+  buildCompanyUserProfileMap,
+  type CompanyUserProfile,
+} from "../lib/company-members";
 import type { IssueChatComment, IssueChatTranscriptEntry } from "../lib/issue-chat-messages";
 import { queryKeys } from "../lib/queryKeys";
 import { cn } from "../lib/utils";
@@ -227,6 +233,8 @@ export interface AssistantChatViewProps {
   companyId?: string | null;
   projectId?: string | null;
   currentUserId?: string | null;
+  userLabelMap?: ReadonlyMap<string, string> | null;
+  userProfileMap?: ReadonlyMap<string, CompanyUserProfile> | null;
   backgroundWorkChildren?: IssueRelationIssueSummary[];
   suppressIssueStatusNotices?: boolean;
   companyName?: string | null;
@@ -240,6 +248,8 @@ export interface AssistantChatViewProps {
   loading?: boolean;
   /** Surface a delivery/transport failure inline (CR8). */
   errorText?: string | null;
+  /** Non-error inline notice (e.g. delivered but the agent can't run here). */
+  noticeText?: string | null;
   onRetry?: () => void;
   onSend: (body: string) => Promise<void>;
   onStopRun?: (runId: string) => Promise<void>;
@@ -285,6 +295,8 @@ export function AssistantChatView({
   companyId,
   projectId,
   currentUserId,
+  userLabelMap,
+  userProfileMap,
   backgroundWorkChildren = [],
   suppressIssueStatusNotices,
   companyName = null,
@@ -296,6 +308,7 @@ export function AssistantChatView({
   onAttachImage,
   loading = false,
   errorText,
+  noticeText,
   onRetry,
   onSend,
   onStopRun,
@@ -439,6 +452,17 @@ export function AssistantChatView({
         </div>
       ) : null}
 
+      {noticeText ? (
+        <div
+          role="status"
+          data-testid="assistant-chat-notice"
+          className="mx-4 mt-3 flex items-start gap-2 rounded-md border border-amber-300/70 bg-amber-50/90 px-3 py-2 text-sm text-amber-950 dark:border-amber-500/40 dark:bg-amber-500/10 dark:text-amber-100"
+        >
+          <AlertCircle className="mt-0.5 h-4 w-4 shrink-0 text-amber-600 dark:text-amber-300" />
+          <p className="min-w-0 flex-1 break-words">{noticeText}</p>
+        </div>
+      ) : null}
+
       {loading && comments.length === 0 ? (
         <div
           data-testid="assistant-chat-skeleton"
@@ -452,7 +476,9 @@ export function AssistantChatView({
       ) : (
         <div
           data-testid="selected-agent-chat-body"
-          className="min-w-0 px-4 pb-4 pt-3"
+          // Own scroll container: chat scrolling (including the initial
+          // scroll-to-latest) must never move the page or the sidebar.
+          className="min-h-0 min-w-0 flex-1 overflow-y-auto px-4 pb-4 pt-3"
         >
           <IssueChatThread
             preset="assistant"
@@ -469,6 +495,8 @@ export function AssistantChatView({
             projectId={projectId}
             agentMap={agentMap}
             currentUserId={currentUserId}
+            userLabelMap={userLabelMap}
+            userProfileMap={userProfileMap}
             backgroundWorkChildren={backgroundWorkChildren}
             suppressIssueStatusNotices={suppressIssueStatusNotices}
             mentions={mentions}
@@ -558,8 +586,23 @@ export function AssistantChat({
   }, [agents, preferredTargetAgentId, targetAgentId]);
 
   const [errorText, setErrorText] = useState<string | null>(null);
+  const [noticeText, setNoticeText] = useState<string | null>(null);
   const [pendingComments, setPendingComments] = useState<PendingAssistantChatComment[]>([]);
 
+  // Resolve human author names/avatars (issue-chat parity: "Dotta", not "You").
+  const { data: companyMembers } = useQuery({
+    queryKey: queryKeys.access.companyUserDirectory(companyId),
+    queryFn: () => accessApi.listUserDirectory(companyId),
+  });
+  const userLabelMap = useMemo(
+    () => buildCompanyUserLabelMap(companyMembers?.users),
+    [companyMembers?.users],
+  );
+  const userProfileMap = useMemo(
+    () => buildCompanyUserProfileMap(companyMembers?.users),
+    [companyMembers?.users],
+  );
+
   const liveRunsQuery = useQuery({
     queryKey: targetAgentId
       ? queryKeys.issues.selectedAgentChatLiveRuns(issueId, targetAgentId)
@@ -655,6 +698,7 @@ export function AssistantChat({
   const handleSend = useCallback(
     async (body: string) => {
       setErrorText(null);
+      setNoticeText(null);
       const optimistic = createOptimisticComment({
         issueId,
         companyId,
@@ -676,6 +720,14 @@ export function AssistantChat({
               : pending,
           ),
         );
+        if (response.wake?.suppressed) {
+          const agentName = response.targetAgent?.name ?? "The agent";
+          setNoticeText(
+            response.wake.reason === "worktree_instance"
+              ? `Message saved, but agent runs are disabled on this worktree instance — ${agentName} won't reply here.`
+              : `Message saved, but agent runs are paused on this instance right now — ${agentName} can't reply yet.`,
+          );
+        }
         await onMessageSent?.();
         invalidateRuns();
       } catch (err) {
@@ -784,6 +836,8 @@ export function AssistantChat({
       companyId={companyId}
       projectId={projectId}
       currentUserId={currentUserId}
+      userLabelMap={userLabelMap}
+      userProfileMap={userProfileMap}
       backgroundWorkChildren={backgroundWorkChildren}
       suppressIssueStatusNotices
       companyName={companyName}
@@ -795,6 +849,7 @@ export function AssistantChat({
       onAttachImage={handleAttachFile}
       loading={commentsQuery.isLoading}
       errorText={errorText}
+      noticeText={noticeText}
       onRetry={errorText ? () => setErrorText(null) : undefined}
       onSend={handleSend}
       onStopRun={handleStopRun}
diff --git a/ui/src/components/FeedCard.tsx b/ui/src/components/FeedCard.tsx
index 099071969a1..0040b6e36c7 100644
--- a/ui/src/components/FeedCard.tsx
+++ b/ui/src/components/FeedCard.tsx
@@ -287,6 +287,7 @@ function resolveContent(
   agentMap: Map<string, Agent>,
   entityNameMap: Map<string, string>,
   entityTitleMap: Map<string, string> | undefined,
+  boardChatIssueRefs: ReadonlyMap<string, string> | undefined,
 ): CardContent {
   const details = event.details as Record<string, unknown> | null;
   const actor = event.actorType === "agent" ? agentMap.get(event.actorId) ?? null : null;
@@ -319,9 +320,18 @@ function resolveContent(
   const approvalAgentName = approvalAgentId ? agentMap.get(approvalAgentId)?.name ?? null : null;
   const approvalType = details?.type as string | undefined;
 
+  // Conference Room conversations are backed by board_chat issues that are
+  // hidden from the regular issues surface — deep-link them to the room, not
+  // to /issues/<uuid> (PAP-13345).
+  const boardChatRef = event.entityType === "issue"
+    ? boardChatIssueRefs?.get(event.entityId) ?? null
+    : null;
+
   const link = isHeartbeatEvent && heartbeatAgentId
     ? `/agents/${heartbeatAgentId}/runs/${event.entityId}`
-    : event.entityType === "issue"
+    : boardChatRef
+      ? `/board-chat/${boardChatRef}`
+      : event.entityType === "issue"
       ? isDocEvent && docKey
         ? `/issues/${issueSlug}#document-${encodeURIComponent(docKey)}`
         : `/issues/${issueSlug}`
@@ -401,6 +411,9 @@ interface FeedCardProps {
   agentMap: Map<string, Agent>;
   entityNameMap: Map<string, string>;
   entityTitleMap?: Map<string, string>;
+  /** Conference Room issue id → conversation ref; events on these issues
+   *  deep-link to /board-chat/{ref} instead of the hidden issue page. */
+  boardChatIssueRefs?: ReadonlyMap<string, string>;
   /** Retained for call-site compatibility; no longer read — the collapsed
    *  card always shows the event-derived status. Lifecycle aggregation (a
    *  later pass) will pass the live status through its own wrapper. */
@@ -420,13 +433,14 @@ export function FeedCard({
   agentMap,
   entityNameMap,
   entityTitleMap,
+  boardChatIssueRefs,
   isActive = false,
   isMuted = false,
   isPinned = false,
   className,
 }: FeedCardProps) {
   const details = event.details as Record<string, unknown> | null;
-  const content = resolveContent(event, agentMap, entityNameMap, entityTitleMap);
+  const content = resolveContent(event, agentMap, entityNameMap, entityTitleMap, boardChatIssueRefs);
   const verb = formatVerb(event.action, details, isPinned ? "pinned" : "chronological");
   const iconSpec = getIconSpec(event, details, isActive);
 
diff --git a/ui/src/components/IssueChatThread.test.tsx b/ui/src/components/IssueChatThread.test.tsx
index 0b77e486a8d..66e3d4293d4 100644
--- a/ui/src/components/IssueChatThread.test.tsx
+++ b/ui/src/components/IssueChatThread.test.tsx
@@ -497,7 +497,7 @@ describe("IssueChatThread", () => {
     });
   });
 
-  it("renders assistant preset turns as compact rows and starts live reasoning collapsed", async () => {
+  it("renders assistant preset turns with issue-chat density and starts live reasoning collapsed", async () => {
     const root = createRoot(container);
     const transcriptsByRunId = new Map<string, readonly IssueChatTranscriptEntry[]>([
       [
@@ -561,7 +561,8 @@ describe("IssueChatThread", () => {
     });
 
     const viewport = container.querySelector('[data-testid="thread-viewport"]') as HTMLDivElement | null;
-    expect(viewport?.className).toContain("space-y-3");
+    // Comfortable (issue-chat) density: full spacing, not the old compact rows.
+    expect(viewport?.className).toContain("space-y-4");
     const workingButton = Array.from(container.querySelectorAll("button")).find(
       (element) => element.textContent?.includes("Working"),
     );
diff --git a/ui/src/components/chat-thread-presets.test.ts b/ui/src/components/chat-thread-presets.test.ts
index 35019849d65..3660b76ac68 100644
--- a/ui/src/components/chat-thread-presets.test.ts
+++ b/ui/src/components/chat-thread-presets.test.ts
@@ -33,7 +33,8 @@ describe("resolveIssueChatThreadPreset", () => {
   it("maps the assistant preset to the lightweight chat defaults", () => {
     expect(resolveIssueChatThreadPreset("assistant")).toMatchObject({
       preset: "assistant",
-      density: "compact",
+      // Comfortable = issue-chat message rendering (own messages right/blue).
+      density: "comfortable",
       workingIndicator: "collapsed",
       variant: "full",
       showComposer: true,
diff --git a/ui/src/components/chat-thread-presets.ts b/ui/src/components/chat-thread-presets.ts
index 6bfd21ed8ba..f05149f6544 100644
--- a/ui/src/components/chat-thread-presets.ts
+++ b/ui/src/components/chat-thread-presets.ts
@@ -65,7 +65,9 @@ const ISSUE_CHAT_THREAD_PRESETS: Record<IssueChatThreadPresetName, IssueChatThre
     composerSingleLine: false,
   },
   assistant: {
-    density: "compact",
+    // Comfortable density matches the issue-chat message rendering: the
+    // board user's own messages are right-aligned blue bubbles (PAP-13345).
+    density: "comfortable",
     workingIndicator: "collapsed",
     variant: "full",
     showComposer: true,