diff --git a/apps/web/src/components/Sidebar.logic.test.ts b/apps/web/src/components/Sidebar.logic.test.ts
index 634d91e9d..9412d64eb 100644
--- a/apps/web/src/components/Sidebar.logic.test.ts
+++ b/apps/web/src/components/Sidebar.logic.test.ts
@@ -1,6 +1,7 @@
 import { describe, expect, it } from "vitest";
 
 import {
+  getProjectIdsWithRunningThreads,
   hasUnseenCompletion,
   resolveThreadStatusPill,
   shouldClearThreadSelectionOnMouseDown,
@@ -154,3 +155,59 @@ describe("resolveThreadStatusPill", () => {
     ).toMatchObject({ label: "Completed", pulse: false });
   });
 });
+
+describe("getProjectIdsWithRunningThreads", () => {
+  it("collects the project ids that have a running thread", () => {
+    expect(
+      getProjectIdsWithRunningThreads([
+        {
+          projectId: "project-1" as never,
+          session: {
+            provider: "codex" as const,
+            status: "running" as const,
+            createdAt: "2026-03-09T10:00:00.000Z",
+            updatedAt: "2026-03-09T10:00:00.000Z",
+            orchestrationStatus: "running" as const,
+          },
+        },
+        {
+          projectId: "project-2" as never,
+          session: {
+            provider: "codex" as const,
+            status: "ready" as const,
+            createdAt: "2026-03-09T10:00:00.000Z",
+            updatedAt: "2026-03-09T10:00:00.000Z",
+            orchestrationStatus: "ready" as const,
+          },
+        },
+      ]),
+    ).toEqual(new Set(["project-1"]));
+  });
+
+  it("ignores non-running sessions", () => {
+    expect(
+      getProjectIdsWithRunningThreads([
+        {
+          projectId: "project-2" as never,
+          session: {
+            provider: "codex" as const,
+            status: "running" as const,
+            createdAt: "2026-03-09T10:00:00.000Z",
+            updatedAt: "2026-03-09T10:00:00.000Z",
+            orchestrationStatus: "running" as const,
+          },
+        },
+        {
+          projectId: "project-3" as never,
+          session: {
+            provider: "codex" as const,
+            status: "ready" as const,
+            createdAt: "2026-03-09T10:00:00.000Z",
+            updatedAt: "2026-03-09T10:00:00.000Z",
+            orchestrationStatus: "ready" as const,
+          },
+        },
+      ]),
+    ).toEqual(new Set(["project-2"]));
+  });
+});
diff --git a/apps/web/src/components/Sidebar.logic.ts b/apps/web/src/components/Sidebar.logic.ts
index f1afa0f64..a07741b69 100644
--- a/apps/web/src/components/Sidebar.logic.ts
+++ b/apps/web/src/components/Sidebar.logic.ts
@@ -21,6 +21,20 @@ type ThreadStatusInput = Pick<
   "interactionMode" | "latestTurn" | "lastVisitedAt" | "proposedPlans" | "session"
 >;
 
+type ProjectActivityThread = Pick<Thread, "projectId" | "session">;
+
+export function getProjectIdsWithRunningThreads(
+  threads: readonly ProjectActivityThread[],
+): ReadonlySet<Thread["projectId"]> {
+  const projectIds = new Set<Thread["projectId"]>();
+  for (const thread of threads) {
+    if (thread.session?.status === "running") {
+      projectIds.add(thread.projectId);
+    }
+  }
+  return projectIds;
+}
+
 export function hasUnseenCompletion(thread: ThreadStatusInput): boolean {
   if (!thread.latestTurn?.completedAt) return false;
   const completedAt = Date.parse(thread.latestTurn.completedAt);
diff --git a/apps/web/src/components/Sidebar.tsx b/apps/web/src/components/Sidebar.tsx
index 8b68c3b80..4d630669a 100644
--- a/apps/web/src/components/Sidebar.tsx
+++ b/apps/web/src/components/Sidebar.tsx
@@ -83,7 +83,11 @@ import {
 import { useThreadSelectionStore } from "../threadSelectionStore";
 import { formatWorktreePathForDisplay, getOrphanedWorktreePathForThread } from "../worktreeCleanup";
 import { isNonEmpty as isNonEmptyString } from "effect/String";
-import { resolveThreadStatusPill, shouldClearThreadSelectionOnMouseDown } from "./Sidebar.logic";
+import {
+  getProjectIdsWithRunningThreads,
+  resolveThreadStatusPill,
+  shouldClearThreadSelectionOnMouseDown,
+} from "./Sidebar.logic";
 
 const EMPTY_KEYBINDINGS: ResolvedKeybindingsConfig = [];
 const THREAD_PREVIEW_LIMIT = 6;
@@ -324,6 +328,10 @@ export default function Sidebar() {
     }
     return map;
   }, [threads]);
+  const projectIdsWithRunningThreads = useMemo(
+    () => getProjectIdsWithRunningThreads(threads),
+    [threads],
+  );
   const projectCwdById = useMemo(
     () => new Map(projects.map((project) => [project.id, project.cwd] as const)),
     [projects],
@@ -1422,6 +1430,7 @@ export default function Sidebar() {
                 strategy={verticalListSortingStrategy}
               >
                 {projects.map((project) => {
+                  const projectHasActiveRun = projectIdsWithRunningThreads.has(project.id);
                   const projectThreads = threads
                     .filter((thread) => thread.projectId === project.id)
                     .toSorted((a, b) => {
@@ -1465,7 +1474,13 @@ export default function Sidebar() {
                                 }`}
                               />
                               <ProjectFavicon cwd={project.cwd} />
-                              <span className="flex-1 truncate text-xs font-medium text-foreground/90">
+                              <span
+                                className={`flex-1 truncate text-xs font-medium ${
+                                  projectHasActiveRun
+                                    ? "project-title-shimmer text-foreground"
+                                    : "text-foreground/90"
+                                }`}
+                              >
                                 {project.name}
                               </span>
                             </SidebarMenuButton>
diff --git a/apps/web/src/index.css b/apps/web/src/index.css
index 228179161..9faa311e5 100644
--- a/apps/web/src/index.css
+++ b/apps/web/src/index.css
@@ -4,6 +4,7 @@
 
 @theme inline {
   --animate-skeleton: skeleton 2s -1s infinite linear;
+  --animate-project-title-shimmer: project-title-shimmer 2.6s ease-in-out infinite;
   --color-warning-foreground: var(--warning-foreground);
   --color-warning: var(--warning);
   --color-success-foreground: var(--success-foreground);
@@ -41,6 +42,15 @@
       background-position: -200% 0;
     }
   }
+
+  @keyframes project-title-shimmer {
+    0% {
+      background-position: 200% 50%;
+    }
+    100% {
+      background-position: -20% 50%;
+    }
+  }
 }
 
 @layer base {
@@ -212,6 +222,43 @@ input {
   display: none;
 }
 
+.project-title-shimmer {
+  animation: var(--animate-project-title-shimmer);
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .project-title-shimmer {
+    animation: none;
+  }
+}
+
+@supports ((-webkit-background-clip: text) or (background-clip: text)) {
+  .project-title-shimmer {
+    background-image: linear-gradient(
+      112deg,
+      var(--foreground) 0%,
+      var(--foreground) 43%,
+      var(--color-sky-300) 48%,
+      var(--color-sky-500) 50%,
+      var(--color-sky-300) 52%,
+      var(--foreground) 57%,
+      var(--foreground) 100%
+    );
+    background-size: 220% 100%;
+    background-position: 200% 50%;
+    color: transparent;
+    -webkit-background-clip: text;
+    background-clip: text;
+    -webkit-text-fill-color: transparent;
+  }
+
+  @media (prefers-reduced-motion: reduce) {
+    .project-title-shimmer {
+      background-position: 50% 50%;
+    }
+  }
+}
+
 /* Terminal drawer scrollbar parity with chat */
 .thread-terminal-drawer .xterm .xterm-scrollable-element > .scrollbar.vertical {
   width: 6px !important;