diff --git a/packages/agent-graph/src/ui/GraphControls.tsx b/packages/agent-graph/src/ui/GraphControls.tsx
index 45bd4361..fb5806eb 100644
--- a/packages/agent-graph/src/ui/GraphControls.tsx
+++ b/packages/agent-graph/src/ui/GraphControls.tsx
@@ -178,10 +178,10 @@ function ToolbarToggle({
   return (
     <button
       onClick={onClick}
-      className={`flex items-center gap-1 rounded-md px-2 py-1 text-[11px] font-mono transition-colors cursor-pointer
+      className={`flex items-center gap-1.5 rounded-md px-2.5 py-1.5 text-[11px] font-mono transition-all cursor-pointer border
         ${active
-          ? 'text-[#aaeeff] bg-[rgba(100,200,255,0.12)]'
-          : 'text-[#66ccff50] hover:text-[#66ccff90]'
+          ? 'text-[#aaeeff] bg-[rgba(100,200,255,0.18)] border-[rgba(100,200,255,0.3)] shadow-[0_0_6px_rgba(100,200,255,0.15)]'
+          : 'text-[#66ccff40] bg-transparent border-transparent hover:text-[#66ccff70] hover:border-[rgba(100,200,255,0.1)]'
         }`}
     >
       {icon}
diff --git a/src/renderer/components/team/dialogs/TaskDetailDialog.tsx b/src/renderer/components/team/dialogs/TaskDetailDialog.tsx
index 7831af44..1239b33b 100644
--- a/src/renderer/components/team/dialogs/TaskDetailDialog.tsx
+++ b/src/renderer/components/team/dialogs/TaskDetailDialog.tsx
@@ -44,7 +44,11 @@ import {
   TASK_STATUS_LABELS,
   TASK_STATUS_STYLES,
 } from '@renderer/utils/memberHelpers';
-import { buildTaskChangeRequestOptions, deriveTaskSince } from '@renderer/utils/taskChangeRequest';
+import {
+  buildTaskChangeRequestOptions,
+  buildTaskChangeSignature,
+  deriveTaskSince,
+} from '@renderer/utils/taskChangeRequest';
 import { linkifyTaskIdsInMarkdown, parseTaskLinkHref } from '@renderer/utils/taskReferenceUtils';
 import { isLeadMember } from '@shared/utils/leadDetection';
 import { getTaskKanbanColumn } from '@shared/utils/reviewState';
@@ -78,6 +82,8 @@ import {
   X,
 } from 'lucide-react';
 
+const TASK_CHANGES_AUTO_REFRESH_MS = 20_000;
+
 import { SourceMessageAttachments } from '../attachments/SourceMessageAttachments';
 
 import { WorkflowTimeline } from './StatusHistoryTimeline';
@@ -154,6 +160,9 @@ export const TaskDetailDialog = ({
   const [taskChangesFiles, setTaskChangesFiles] = useState<FileChangeSummary[] | null>(null);
   const [taskChangesLoading, setTaskChangesLoading] = useState(false);
   const [taskChangesError, setTaskChangesError] = useState<string | null>(null);
+  const loadedTaskChangeSummaryKeyRef = useRef<string | null>(null);
+  const taskChangesLoadInFlightRef = useRef(false);
+  const currentTaskChangeSummaryKeyRef = useRef<string | null>(null);
 
   // Inline editing: subject
   const [editingSubject, setEditingSubject] = useState(false);
@@ -323,6 +332,17 @@ export const TaskDetailDialog = ({
     () => (currentTask ? buildTaskChangeRequestOptions(currentTask) : null),
     [currentTask]
   );
+  const taskChangeRequestSignature = useMemo(
+    () => (taskChangeRequestOptions ? buildTaskChangeSignature(taskChangeRequestOptions) : null),
+    [taskChangeRequestOptions]
+  );
+  const currentTaskChangeSummaryKey = useMemo(
+    () =>
+      currentTask
+        ? `${teamName}:${currentTask.id}:${taskChangeRequestSignature ?? 'default'}`
+        : null,
+    [currentTask, teamName, taskChangeRequestSignature]
+  );
   const taskChangeSummaryOptions = useMemo(
     () =>
       currentTask
@@ -335,6 +355,10 @@ export const TaskDetailDialog = ({
   );
   const setTaskNeedsClarification = useStore((s) => s.setTaskNeedsClarification);
 
+  useEffect(() => {
+    currentTaskChangeSummaryKeyRef.current = currentTaskChangeSummaryKey;
+  }, [currentTaskChangeSummaryKey]);
+
   const loadTaskChangeSummary = useCallback(
     async (forceFresh = false): Promise<TaskChangeSetV2 | null> => {
       if (
@@ -355,71 +379,109 @@ export const TaskDetailDialog = ({
     [canShowTaskChanges, currentTask, onViewChanges, taskChangeSummaryOptions, teamName, variant]
   );
 
+  const syncTaskChangeSummaryResult = useCallback(
+    (data: TaskChangeSetV2 | null) => {
+      setTaskChangesFiles(data?.files ?? null);
+      if (currentTask && taskChangeRequestOptions) {
+        recordTaskHasChanges(
+          teamName,
+          currentTask.id,
+          taskChangeRequestOptions,
+          !!data?.files.length
+        );
+      }
+      const nextPresence = data ? resolveTaskChangePresenceFromResult(data) : null;
+      if (currentTask && nextPresence) {
+        setSelectedTeamTaskChangePresence(teamName, currentTask.id, nextPresence);
+      }
+    },
+    [
+      currentTask,
+      recordTaskHasChanges,
+      setSelectedTeamTaskChangePresence,
+      taskChangeRequestOptions,
+      teamName,
+    ]
+  );
+
+  const requestTaskChangeSummary = useCallback(
+    async ({
+      forceFresh = false,
+      showSpinner = false,
+      preserveFilesOnError = false,
+    }: {
+      forceFresh?: boolean;
+      showSpinner?: boolean;
+      preserveFilesOnError?: boolean;
+    } = {}): Promise<void> => {
+      const requestKey = currentTaskChangeSummaryKeyRef.current;
+      if (taskChangesLoadInFlightRef.current) return;
+      if (
+        !requestKey ||
+        !currentTask ||
+        variant !== 'team' ||
+        !canShowTaskChanges ||
+        !onViewChanges
+      )
+        return;
+
+      taskChangesLoadInFlightRef.current = true;
+      if (showSpinner) {
+        setTaskChangesLoading(true);
+      }
+      setTaskChangesError(null);
+
+      try {
+        const data = await loadTaskChangeSummary(forceFresh);
+        if (currentTaskChangeSummaryKeyRef.current !== requestKey) {
+          return;
+        }
+        syncTaskChangeSummaryResult(data);
+      } catch (error) {
+        if (currentTaskChangeSummaryKeyRef.current !== requestKey) {
+          return;
+        }
+        if (!preserveFilesOnError) {
+          setTaskChangesFiles(null);
+        }
+        setTaskChangesError(
+          error instanceof Error ? error.message : 'Failed to load task changes summary'
+        );
+      } finally {
+        taskChangesLoadInFlightRef.current = false;
+        if (showSpinner) {
+          setTaskChangesLoading(false);
+        }
+      }
+    },
+    [
+      canShowTaskChanges,
+      currentTask,
+      loadTaskChangeSummary,
+      onViewChanges,
+      syncTaskChangeSummaryResult,
+      variant,
+    ]
+  );
+
   useEffect(() => {
     if (variant !== 'team') return;
     if (!open || !currentTask || !canShowTaskChanges || !onViewChanges || !changesSectionOpen)
       return;
 
-    let cancelled = false;
+    const summaryKey = currentTaskChangeSummaryKey;
+    if (loadedTaskChangeSummaryKeyRef.current === summaryKey) {
+      return;
+    }
+    loadedTaskChangeSummaryKeyRef.current = summaryKey;
+
     // Show full loading state only when no files are cached yet;
     // otherwise let the refresh button spinner indicate background reload.
-    if (!taskChangesFiles || taskChangesFiles.length === 0) {
-      setTaskChangesLoading(true);
-    }
-    setTaskChangesError(null);
-    void loadTaskChangeSummary()
-      .then((data) => {
-        if (!cancelled) {
-          setTaskChangesFiles(data?.files ?? null);
-          if (currentTask && taskChangeRequestOptions) {
-            recordTaskHasChanges(
-              teamName,
-              currentTask.id,
-              taskChangeRequestOptions,
-              !!data?.files.length
-            );
-          }
-          const nextPresence = data ? resolveTaskChangePresenceFromResult(data) : null;
-          if (currentTask && nextPresence) {
-            setSelectedTeamTaskChangePresence(teamName, currentTask.id, nextPresence);
-          }
-        }
-      })
-      .catch((error) => {
-        if (!cancelled) {
-          setTaskChangesFiles(null);
-          setTaskChangesError(
-            error instanceof Error ? error.message : 'Failed to load task changes summary'
-          );
-        }
-      })
-      .finally(() => {
-        if (!cancelled) setTaskChangesLoading(false);
-      });
-
-    void loadTaskChangeSummary(true)
-      .then((data) => {
-        if (!cancelled && data) {
-          setTaskChangesFiles(data.files);
-          if (currentTask && taskChangeRequestOptions) {
-            recordTaskHasChanges(
-              teamName,
-              currentTask.id,
-              taskChangeRequestOptions,
-              data.files.length > 0
-            );
-          }
-          const nextPresence = resolveTaskChangePresenceFromResult(data);
-          if (currentTask && nextPresence) {
-            setSelectedTeamTaskChangePresence(teamName, currentTask.id, nextPresence);
-          }
-        }
-      })
-      .catch(() => undefined);
-
-    return () => {
-      cancelled = true;
-    };
+    void requestTaskChangeSummary({
+      forceFresh: false,
+      showSpinner: !taskChangesFiles || taskChangesFiles.length === 0,
+      preserveFilesOnError: false,
+    });
   }, [
     changesSectionOpen,
     open,
@@ -427,50 +489,54 @@ export const TaskDetailDialog = ({
     canShowTaskChanges,
     teamName,
     onViewChanges,
-    taskSince,
+    currentTaskChangeSummaryKey,
+    taskChangeRequestSignature,
     variant,
-    loadTaskChangeSummary,
+    requestTaskChangeSummary,
+    taskChangesFiles,
   ]);
 
-  const handleRefreshChanges = useCallback(() => {
-    if (!currentTask || variant !== 'team' || !canShowTaskChanges || !onViewChanges) return;
-    setTaskChangesLoading(true);
-    setTaskChangesError(null);
-    void loadTaskChangeSummary(true)
-      .then((data) => {
-        setTaskChangesFiles(data?.files ?? null);
-        if (currentTask && taskChangeRequestOptions) {
-          recordTaskHasChanges(
-            teamName,
-            currentTask.id,
-            taskChangeRequestOptions,
-            !!data?.files.length
-          );
-        }
-        const nextPresence = data ? resolveTaskChangePresenceFromResult(data) : null;
-        if (currentTask && nextPresence) {
-          setSelectedTeamTaskChangePresence(teamName, currentTask.id, nextPresence);
-        }
-      })
-      .catch((error) => {
-        setTaskChangesFiles(null);
-        setTaskChangesError(
-          error instanceof Error ? error.message : 'Failed to load task changes summary'
-        );
-      })
-      .finally(() => setTaskChangesLoading(false));
+  useEffect(() => {
+    if (!open || !changesSectionOpen) {
+      loadedTaskChangeSummaryKeyRef.current = null;
+    }
+  }, [open, changesSectionOpen]);
+
+  useEffect(() => {
+    if (variant !== 'team') return;
+    if (!open || !currentTask || !canShowTaskChanges || !onViewChanges || !changesSectionOpen) {
+      return;
+    }
+
+    const timer = window.setInterval(() => {
+      void requestTaskChangeSummary({
+        forceFresh: true,
+        showSpinner: false,
+        preserveFilesOnError: true,
+      });
+    }, TASK_CHANGES_AUTO_REFRESH_MS);
+
+    return () => {
+      window.clearInterval(timer);
+    };
   }, [
+    changesSectionOpen,
+    open,
     currentTask,
     canShowTaskChanges,
     onViewChanges,
-    loadTaskChangeSummary,
-    recordTaskHasChanges,
-    setSelectedTeamTaskChangePresence,
-    taskChangeRequestOptions,
-    teamName,
+    requestTaskChangeSummary,
     variant,
   ]);
 
+  const handleRefreshChanges = useCallback(() => {
+    void requestTaskChangeSummary({
+      forceFresh: true,
+      showSpinner: true,
+      preserveFilesOnError: false,
+    });
+  }, [requestTaskChangeSummary]);
+
   const handleDependencyClick = (taskId: string): void => {
     // Resolve short displayId (e.g. "8ce74455") to full UUID via taskMap,
     // since kanban cards use the full UUID in data-task-id.
diff --git a/src/renderer/components/team/review/FileSectionDiff.tsx b/src/renderer/components/team/review/FileSectionDiff.tsx
index 846694ac..a25a2dcc 100644
--- a/src/renderer/components/team/review/FileSectionDiff.tsx
+++ b/src/renderer/components/team/review/FileSectionDiff.tsx
@@ -4,6 +4,10 @@ import { CodeMirrorDiffView } from './CodeMirrorDiffView';
 import { DiffErrorBoundary } from './DiffErrorBoundary';
 import { FileSectionPlaceholder } from './FileSectionPlaceholder';
 import { ReviewDiffContent } from './ReviewDiffContent';
+import {
+  shouldRenderCodeMirrorReviewDiff,
+  shouldRenderSnippetReviewPreview,
+} from './reviewDiffSafety';
 
 import type { EditorView } from '@codemirror/view';
 import type { FileChangeWithContent } from '@shared/types';
@@ -47,6 +51,7 @@ export const FileSectionDiff = ({
 }: FileSectionDiffProps): React.ReactElement => {
   const localEditorViewRef = useRef<EditorView | null>(null);
   const sentinelRef = useRef<HTMLDivElement>(null);
+  const canRenderSnippetPreview = shouldRenderSnippetReviewPreview(file.snippets);
 
   // Notify parent whenever CodeMirrorDiffView creates or destroys its EditorView.
   // This fires on every editor lifecycle event: initial mount, key-change remount,
@@ -87,7 +92,11 @@ export const FileSectionDiff = ({
 
     return (
       <div className="overflow-auto">
-        <ReviewDiffContent file={file} />
+        {canRenderSnippetPreview ? (
+          <ReviewDiffContent file={file} />
+        ) : (
+          <OversizedDiffNotice message="Diff preview skipped because the change is too large to render safely." />
+        )}
         <div ref={sentinelRef} className="h-1 shrink-0" />
       </div>
     );
@@ -115,18 +124,29 @@ export const FileSectionDiff = ({
   //   pretend it's empty — fall back to snippet-level diff.
   const canRenderCodeMirror =
     resolvedModified !== null && (file.isNewFile || resolvedOriginal !== null);
+  const originalForDiff = file.isNewFile ? '' : (resolvedOriginal ?? '');
+  const canRenderCodeMirrorSafely =
+    canRenderCodeMirror &&
+    shouldRenderCodeMirrorReviewDiff(originalForDiff, resolvedModified ?? '');
 
-  if (!canRenderCodeMirror) {
+  if (!canRenderCodeMirrorSafely) {
     return (
       <div className="overflow-auto">
-        <ReviewDiffContent file={file} />
+        <OversizedDiffNotice
+          message={
+            canRenderCodeMirror && !canRenderSnippetPreview
+              ? 'Full diff skipped because it is large enough to risk a renderer out-of-memory crash.'
+              : canRenderCodeMirror
+                ? 'Large diff opened in safe preview mode to avoid a renderer out-of-memory crash.'
+                : 'Diff preview skipped because the available change data is too large to render safely.'
+          }
+        />
+        {canRenderSnippetPreview ? <ReviewDiffContent file={file} /> : null}
         <div ref={sentinelRef} className="h-1 shrink-0" />
       </div>
     );
   }
 
-  const originalForDiff = file.isNewFile ? '' : (resolvedOriginal ?? '');
-
   return (
     <div className="overflow-auto">
       {isMissingOnDisk && (
@@ -170,3 +190,11 @@ export const FileSectionDiff = ({
     </div>
   );
 };
+
+function OversizedDiffNotice({ message }: { message: string }): React.ReactElement {
+  return (
+    <div className="border-b border-border bg-amber-500/10 px-4 py-3 text-xs text-amber-300">
+      {message}
+    </div>
+  );
+}
diff --git a/src/renderer/components/team/review/reviewDiffSafety.ts b/src/renderer/components/team/review/reviewDiffSafety.ts
new file mode 100644
index 00000000..1b9f1f14
--- /dev/null
+++ b/src/renderer/components/team/review/reviewDiffSafety.ts
@@ -0,0 +1,59 @@
+import type { SnippetDiff } from '@shared/types/review';
+
+const MAX_CODEMIRROR_DIFF_COMBINED_BYTES = 2 * 1024 * 1024;
+const MAX_CODEMIRROR_DIFF_LINE_PRODUCT = 1_000_000;
+const MAX_SNIPPET_PREVIEW_COMBINED_BYTES = 512 * 1024;
+const MAX_SNIPPET_PREVIEW_TOTAL_LINES = 4_000;
+
+function countLinesUpTo(text: string, limit: number): number {
+  let lines = 1;
+  for (let i = 0; i < text.length; i++) {
+    if (text.charCodeAt(i) === 10) {
+      lines++;
+      if (lines > limit) {
+        return lines;
+      }
+    }
+  }
+  return lines;
+}
+
+export function shouldRenderCodeMirrorReviewDiff(original: string, modified: string): boolean {
+  const combinedBytes = original.length + modified.length;
+  if (combinedBytes > MAX_CODEMIRROR_DIFF_COMBINED_BYTES) {
+    return false;
+  }
+
+  const oldLines = countLinesUpTo(original, MAX_CODEMIRROR_DIFF_LINE_PRODUCT + 1);
+  const newLines = countLinesUpTo(modified, MAX_CODEMIRROR_DIFF_LINE_PRODUCT + 1);
+
+  return oldLines * newLines <= MAX_CODEMIRROR_DIFF_LINE_PRODUCT;
+}
+
+export function shouldRenderSnippetReviewPreview(snippets: SnippetDiff[]): boolean {
+  let totalBytes = 0;
+  let totalLines = 0;
+
+  for (const snippet of snippets) {
+    if (snippet.isError) {
+      continue;
+    }
+
+    totalBytes += snippet.oldString.length + snippet.newString.length;
+    if (totalBytes > MAX_SNIPPET_PREVIEW_COMBINED_BYTES) {
+      return false;
+    }
+
+    totalLines += countLinesUpTo(snippet.oldString, MAX_SNIPPET_PREVIEW_TOTAL_LINES);
+    if (totalLines > MAX_SNIPPET_PREVIEW_TOTAL_LINES) {
+      return false;
+    }
+
+    totalLines += countLinesUpTo(snippet.newString, MAX_SNIPPET_PREVIEW_TOTAL_LINES);
+    if (totalLines > MAX_SNIPPET_PREVIEW_TOTAL_LINES) {
+      return false;
+    }
+  }
+
+  return true;
+}
diff --git a/src/renderer/store/index.ts b/src/renderer/store/index.ts
index 3e7e388c..5f7dd39a 100644
--- a/src/renderer/store/index.ts
+++ b/src/renderer/store/index.ts
@@ -143,6 +143,8 @@ export function initializeNotificationListeners(): () => void {
   cleanupFns.push(() => {
     if (cliStatusTimer) clearTimeout(cliStatusTimer);
   });
+  // This lightweight renderer-side poll keeps visible in-progress task badges fresh.
+  // It is intentionally independent from the backend log-source tracking feature flag below.
   const inProgressChangePresencePollTimer = setInterval(() => {
     void pollVisibleTeamInProgressChangePresence();
   }, IN_PROGRESS_CHANGE_PRESENCE_POLL_MS);
diff --git a/test/renderer/components/reviewDiffSafety.test.ts b/test/renderer/components/reviewDiffSafety.test.ts
new file mode 100644
index 00000000..89933141
--- /dev/null
+++ b/test/renderer/components/reviewDiffSafety.test.ts
@@ -0,0 +1,53 @@
+import { describe, expect, it } from 'vitest';
+
+import {
+  shouldRenderCodeMirrorReviewDiff,
+  shouldRenderSnippetReviewPreview,
+} from '@renderer/components/team/review/reviewDiffSafety';
+
+describe('reviewDiffSafety', () => {
+  it('allows regular CodeMirror review diffs', () => {
+    expect(shouldRenderCodeMirrorReviewDiff('line 1\nline 2', 'line 1\nline 3')).toBe(true);
+  });
+
+  it('blocks oversized CodeMirror review diffs by line-product', () => {
+    const original = Array.from({ length: 1200 }, (_, i) => `old ${i}`).join('\n');
+    const modified = Array.from({ length: 1200 }, (_, i) => `new ${i}`).join('\n');
+
+    expect(shouldRenderCodeMirrorReviewDiff(original, modified)).toBe(false);
+  });
+
+  it('allows small snippet previews', () => {
+    expect(
+      shouldRenderSnippetReviewPreview([
+        {
+          filePath: '/tmp/a.ts',
+          oldString: 'const a = 1;\n',
+          newString: 'const a = 2;\n',
+          timestamp: '2026-03-28T10:00:00.000Z',
+          toolUseId: 'tool-1',
+          type: 'edit',
+          replaceAll: false,
+          isError: false,
+        },
+      ])
+    ).toBe(true);
+  });
+
+  it('blocks oversized snippet previews', () => {
+    expect(
+      shouldRenderSnippetReviewPreview([
+        {
+          filePath: '/tmp/big.ts',
+          oldString: '',
+          newString: 'a'.repeat(600 * 1024),
+          timestamp: '2026-03-28T10:00:00.000Z',
+          toolUseId: 'tool-2',
+          type: 'write-update',
+          replaceAll: false,
+          isError: false,
+        },
+      ])
+    ).toBe(false);
+  });
+});