diff --git a/AGENTS.md b/AGENTS.md
index c94ba3881e..358d579e53 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -112,6 +112,7 @@ Additional rules:
 - No `unsafe` code
 - Do not introduce new `unwrap()` or `expect()` in production paths — use `?` and proper error types
 - New public API must have doc comments
+- **DCO Sign-off**: Always sign off your commits (e.g. `git commit -s`) to comply with the Developer Certificate of Origin (DCO) check.
 
 ---
 
diff --git a/desktop/src/features/channels/ui/ChannelScreenHeader.tsx b/desktop/src/features/channels/ui/ChannelScreenHeader.tsx
index a3a8a20231..3bd505aed2 100644
--- a/desktop/src/features/channels/ui/ChannelScreenHeader.tsx
+++ b/desktop/src/features/channels/ui/ChannelScreenHeader.tsx
@@ -4,6 +4,7 @@ import type * as React from "react";
 import { ChatHeader } from "@/features/chat/ui/ChatHeader";
 import type { EphemeralChannelDisplay } from "@/features/channels/lib/ephemeralChannel";
 import type { ActiveDmHeaderParticipant } from "@/features/channels/useActiveChannelHeader";
+import { UserProfilePopover } from "@/features/profile/ui/UserProfilePopover";
 import { getChannelDescription } from "@/features/channels/lib/channelDescription";
 import { getDmParticipantPreview } from "@/features/channels/lib/dmParticipantDisplay";
 import { ChannelHeaderStatusBadge } from "@/features/channels/ui/ChannelHeaderStatusBadge";
@@ -113,6 +114,30 @@ export function ChannelScreenHeader({
             <DmHeaderParticipantStack
               participants={activeDmHeaderParticipants}
             />
+          ) : activeDmHeaderParticipants.length === 1 ? (
+            <UserProfilePopover
+              pubkey={activeDmHeaderParticipants[0].pubkey}
+              hideMessageAction
+            >
+              <button
+                className="flex shrink-0 items-start focus-visible:outline-hidden focus-visible:ring-2 focus-visible:ring-ring rounded-full"
+                type="button"
+                data-testid="chat-header-dm-avatar-button"
+              >
+                <ProfileAvatarWithStatus
+                  avatarClassName="text-xs"
+                  avatarUrl={activeDmAvatarUrl}
+                  className="mr-1.5 h-8 w-8"
+                  geometry={DM_HEADER_AVATAR_STATUS_GEOMETRY}
+                  iconClassName="h-4 w-4"
+                  label={activeChannelTitle}
+                  size={DM_HEADER_AVATAR_SIZE}
+                  status={activeDmPresenceStatus ?? "offline"}
+                  statusTestId="chat-presence-badge"
+                  testId="chat-header-dm-avatar"
+                />
+              </button>
+            </UserProfilePopover>
           ) : (
             <ProfileAvatarWithStatus
               avatarClassName="text-xs"
@@ -137,6 +162,12 @@ export function ChannelScreenHeader({
       title={activeChannelTitle}
       transparentChrome={transparentChrome}
       visibility={activeChannel?.visibility}
+      dmUserPubkey={
+        activeChannel?.channelType === "dm" &&
+        activeDmHeaderParticipants.length === 1
+          ? activeDmHeaderParticipants[0].pubkey
+          : undefined
+      }
     />
   );
 }
@@ -170,12 +201,23 @@ function DmHeaderParticipantStack({
             }),
           }}
         >
-          <UserAvatar
-            avatarUrl={participant.avatarUrl}
-            className="h-8 w-8 text-xs"
-            displayName={participant.displayName}
-            size="sm"
-          />
+          <UserProfilePopover
+            pubkey={participant.pubkey}
+            hideMessageAction
+            triggerElement="span"
+          >
+            <button
+              className="flex shrink-0 items-start focus-visible:outline-hidden focus-visible:ring-2 focus-visible:ring-ring rounded-full"
+              type="button"
+            >
+              <UserAvatar
+                avatarUrl={participant.avatarUrl}
+                className="h-8 w-8 text-xs"
+                displayName={participant.displayName}
+                size="sm"
+              />
+            </button>
+          </UserProfilePopover>
         </div>
       ))}
       {hiddenCount > 0 ? (
diff --git a/desktop/src/features/chat/ui/ChatHeader.tsx b/desktop/src/features/chat/ui/ChatHeader.tsx
index 9ced506751..5f1299a6c5 100644
--- a/desktop/src/features/chat/ui/ChatHeader.tsx
+++ b/desktop/src/features/chat/ui/ChatHeader.tsx
@@ -15,6 +15,7 @@ import { toast } from "sonner";
 
 import type { ChannelType, ChannelVisibility } from "@/shared/api/types";
 import { UpdateIndicator } from "@/features/settings/UpdateIndicator";
+import { UserProfilePopover } from "@/features/profile/ui/UserProfilePopover";
 import { cn } from "@/shared/lib/cn";
 import { channelChrome } from "@/shared/layout/chromeLayout";
 import { Button } from "@/shared/ui/button";
@@ -35,6 +36,7 @@ type ChatHeaderProps = {
   statusBadge?: React.ReactNode;
   /** Render the chrome wrapper without an individual backdrop when a parent supplies shared blur. */
   transparentChrome?: boolean;
+  dmUserPubkey?: string;
 };
 
 const HEADER_ICON_CLASS = "h-4 w-4 text-muted-foreground";
@@ -97,6 +99,7 @@ export function ChatHeader({
   overlaysContent = false,
   statusBadge,
   transparentChrome = false,
+  dmUserPubkey,
 }: ChatHeaderProps) {
   const trimmedDescription = description?.trim() ?? "";
 
@@ -133,27 +136,51 @@ export function ChatHeader({
                 />
               )}
             </div>
-            <h1
-              className={cn(
-                "min-w-0 truncate text-base font-semibold leading-6 tracking-tight",
-                channelType !== "dm" && "translate-y-px",
-              )}
-              data-testid="chat-title"
-              title={trimmedDescription || undefined}
-            >
-              {title}
-            </h1>
-            <Button
-              aria-label={`Copy channel name: ${title}`}
-              className="h-6 w-6 shrink-0 opacity-0 text-muted-foreground transition-opacity hover:text-foreground focus-visible:opacity-100 group-hover/title:opacity-100"
-              onClick={() => void handleCopyTitle()}
-              size="icon-xs"
-              title="Copy channel name"
-              type="button"
-              variant="ghost"
-            >
-              <Copy className="h-3.5 w-3.5" />
-            </Button>
+            {dmUserPubkey ? (
+              <UserProfilePopover
+                pubkey={dmUserPubkey}
+                hideMessageAction
+                triggerElement="span"
+              >
+                <button
+                  className="min-w-0 text-left rounded leading-6 focus-visible:outline-hidden focus-visible:ring-2 focus-visible:ring-ring hover:underline"
+                  type="button"
+                  data-testid="chat-header-title-button"
+                >
+                  <h1
+                    className="min-w-0 truncate text-base font-semibold leading-6 tracking-tight"
+                    data-testid="chat-title"
+                    title={trimmedDescription || undefined}
+                  >
+                    {title}
+                  </h1>
+                </button>
+              </UserProfilePopover>
+            ) : (
+              <h1
+                className={cn(
+                  "min-w-0 truncate text-base font-semibold leading-6 tracking-tight",
+                  channelType !== "dm" && "translate-y-px",
+                )}
+                data-testid="chat-title"
+                title={trimmedDescription || undefined}
+              >
+                {title}
+              </h1>
+            )}
+            {channelType !== "dm" && (
+              <Button
+                aria-label={`Copy channel name: ${title}`}
+                className="h-6 w-6 shrink-0 opacity-0 text-muted-foreground transition-opacity hover:text-foreground focus-visible:opacity-100 group-hover/title:opacity-100"
+                onClick={() => void handleCopyTitle()}
+                size="icon-xs"
+                title="Copy channel name"
+                type="button"
+                variant="ghost"
+              >
+                <Copy className="h-3.5 w-3.5" />
+              </Button>
+            )}
             {statusBadge ? (
               <div className="flex shrink-0 flex-wrap items-center gap-1">
                 {statusBadge}
diff --git a/desktop/src/features/profile/ui/UserProfilePopover.tsx b/desktop/src/features/profile/ui/UserProfilePopover.tsx
index 9161bac302..fa567e7796 100644
--- a/desktop/src/features/profile/ui/UserProfilePopover.tsx
+++ b/desktop/src/features/profile/ui/UserProfilePopover.tsx
@@ -63,6 +63,7 @@ type UserProfilePopoverProps = {
   role?: string;
   /** Value used to generate the BotIdenticon glyph (typically the author name). */
   botIdenticonValue?: string;
+  hideMessageAction?: boolean;
 };
 
 const HOVER_OPEN_DELAY_MS = 500;
@@ -175,6 +176,7 @@ export function UserProfilePopover({
   enableProfilePanel = true,
   role,
   botIdenticonValue,
+  hideMessageAction = false,
 }: UserProfilePopoverProps) {
   const [open, setOpen] = React.useState(false);
   const [pendingAction, setPendingAction] = React.useState<
@@ -260,6 +262,7 @@ export function UserProfilePopover({
   const isCurrentUserOwner = ownsAuthorAgent(profile, currentPubkey);
   const viewerIsOwner = isCurrentUserOwner || isOwner === true;
   const showMessageAction =
+    !hideMessageAction &&
     showProfileActions &&
     !isAgentClassificationPending &&
     (!isBotProfile || viewerIsOwner);