fix(ui): repair control chat metadata handling

CHANGELOG.md

@@ -65,6 +65,7 @@ Docs: https://docs.openclaw.ai
 - Slack/performance: reduce message preparation, stream recipient lookup, and thread-context allocation overhead on Slack reply hot paths. Thanks @vincentkoc.
 - Channels/streaming: cap progress-draft tool lines by default so edited progress boxes avoid jumpy reflow from long wrapped lines.
 - Control UI/chat: add an agent-first filter to the chat session picker, keep chat controls/composer responsive across phone/tablet/desktop widths, keep desktop chat controls on one row, avoid duplicate avatar refreshes during initial chat load, and hide that row while scrolling down the transcript. Thanks @BunsDev.
+- Control UI/chat: strip untrusted sender metadata from live streams and transcript display, preserve canvas preview anchors, and stop operator UI clients from injecting their internal client id as sender identity. Fixes #78739. Thanks @guguangxin-eng, @hclsys, and @BunsDev.
 - Control UI/chat: collapse consecutive duplicate text messages into one bubble with a count so repeated text-only messages stay compact without hiding nearby context.
 - Control UI/chat and Sessions: label inherited thinking defaults separately from explicit overrides while preserving provider-supplied option labels. Fixes #77581. Thanks @BunsDev and @Beandon13.
 - Agents/runtime: add prepared runtime foundation contracts for carrying provider, model, tool, TTS, and outbound runtime facts through later reply-path migrations. Thanks @mcaxtr.

ui/src/ui/chat/build-chat-items.test.ts

@@ -154,7 +154,6 @@ describe("buildChatItems", () => {
     expect(items).toEqual([]);
   });
 
-<<<<<<< fix/control-ui-sender-metadata-stream
   it("suppresses active sender metadata streams before rendering", () => {
     const items = buildChatItems(
       createProps({
@@ -197,7 +196,8 @@ describe("buildChatItems", () => {
     });
 
     expect(groups).toEqual([]);
-=======
+  });
+
   it("renders only the last 100 history messages and shows a hidden-count notice", () => {
     const items = buildChatItems(
       createProps({
@@ -229,7 +229,6 @@ describe("buildChatItems", () => {
     expect(groups.at(-1)?.messages[0].message).toMatchObject({
       content: "message 104",
     });
->>>>>>> main
   });
 
   it("does not collapse duplicate text messages separated by another message", () => {
@@ -312,6 +311,45 @@ describe("buildChatItems", () => {
     expect(firstMessageContent(groups[1]).some((block) => isCanvasBlock(block))).toBe(false);
   });
 
+  it("preserves a metadata-only assistant anchor when lifting canvas previews", () => {
+    const groups = messageGroups({
+      messages: [
+        {
+          id: "assistant-metadata-anchor",
+          role: "assistant",
+          content: SENDER_METADATA_BLOCK,
+          timestamp: 1_000,
+        },
+      ],
+      toolMessages: [
+        {
+          id: "tool-canvas-for-empty-anchor",
+          role: "tool",
+          toolCallId: "call-canvas-empty-anchor",
+          toolName: "canvas_render",
+          content: JSON.stringify({
+            kind: "canvas",
+            view: {
+              backend: "canvas",
+              id: "cv_empty_anchor",
+              url: "/__openclaw__/canvas/documents/cv_empty_anchor/index.html",
+              title: "Empty anchor demo",
+              preferred_height: 320,
+            },
+            presentation: {
+              target: "assistant_message",
+            },
+          }),
+          timestamp: 1_001,
+        },
+      ],
+    });
+
+    expect(
+      groups.some((group) => firstMessageContent(group).some((block) => isCanvasBlock(block))),
+    ).toBe(true);
+  });
+
   it("does not lift generic view handles from non-canvas payloads", () => {
     const groups = messageGroups({
       messages: [

ui/src/ui/chat/build-chat-items.ts

@@ -260,11 +260,18 @@ function sanitizeStreamText(text: string): string {
 }
 
 export function buildChatItems(props: BuildChatItemsProps): Array<ChatItem | MessageGroup> {
-  const items: ChatItem[] = [];
+  let items: ChatItem[] = [];
   const history = (Array.isArray(props.messages) ? props.messages : []).filter(
     (message) => !isAssistantHeartbeatAckForDisplay(message),
   );
   const tools = Array.isArray(props.toolMessages) ? props.toolMessages : [];
+  const liftedCanvasSources = tools
+    .map((tool) => extractChatMessagePreview(tool))
+    .filter((entry) => Boolean(entry)) as Array<{
+    preview: Extract<NonNullable<ToolCard["preview"]>, { kind: "canvas" }>;
+    text: string | null;
+    timestamp: number | null;
+  }>;
   const historyStart = Math.max(0, history.length - CHAT_HISTORY_RENDER_LIMIT);
   if (historyStart > 0) {
     items.push({
@@ -309,7 +316,7 @@ export function buildChatItems(props: BuildChatItemsProps): Array<ChatItem | Mes
     if (props.searchOpen && searchQuery.trim() && !messageMatchesSearchQuery(msg, searchQuery)) {
       continue;
     }
-    if (!hasRenderableNormalizedMessage(msg)) {
+    if (!hasRenderableNormalizedMessage(msg) && normalized.role.toLowerCase() !== "assistant") {
       continue;
     }
 
@@ -319,13 +326,6 @@ export function buildChatItems(props: BuildChatItemsProps): Array<ChatItem | Mes
       message: msg,
     });
   }
-  const liftedCanvasSources = tools
-    .map((tool) => extractChatMessagePreview(tool))
-    .filter((entry) => Boolean(entry)) as Array<{
-    preview: Extract<NonNullable<ToolCard["preview"]>, { kind: "canvas" }>;
-    text: string | null;
-    timestamp: number | null;
-  }>;
   for (const liftedCanvasSource of liftedCanvasSources) {
     const assistantIndex = findNearestAssistantMessageIndex(items, liftedCanvasSource.timestamp);
     if (assistantIndex == null) {
@@ -344,6 +344,9 @@ export function buildChatItems(props: BuildChatItemsProps): Array<ChatItem | Mes
       ),
     };
   }
+  items = items.filter(
+    (item) => item.kind !== "message" || hasRenderableNormalizedMessage(item.message),
+  );
   const segments = props.streamSegments ?? [];
   const maxLen = Math.max(segments.length, tools.length);
   for (let i = 0; i < maxLen; i++) {