From 411cef0008fa8e1e5251a8aae2cc6a215f700a9c Mon Sep 17 00:00:00 2001
From: Alex Southwell <saphid@gmail.com>
Date: Tue, 6 Oct 2026 20:22:39 +1100
Subject: [PATCH] fix(desktop): prevent browser screenshot filename collisions
 (#14784)

---
 apps/desktop/src/preview/Manager.test.ts | 34 ++++++++++++++++++++++++
 apps/desktop/src/preview/Manager.ts      |  2 +-
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/apps/desktop/src/preview/Manager.test.ts b/apps/desktop/src/preview/Manager.test.ts
index 5211d59804f163ef0bd651168fdce0dd94f58db9..bf14a1981f13c72e89881f9b283008760e735d24 100644
--- a/apps/desktop/src/preview/Manager.test.ts
+++ b/apps/desktop/src/preview/Manager.test.ts
@@ -2367,6 +2367,40 @@ describe("PreviewManager", () => {
     ),
   );
 
+  effectIt.effect("preserves both screenshots of the same site in the same millisecond", () =>
+    withManager((manager) =>
+      Effect.gen(function* () {
+        const firstPng = Buffer.from("first-preview-png");
+        const secondPng = Buffer.from("second-preview-png");
+        const pngImage = (png: Buffer) => ({
+          toPNG: () => png,
+          toJPEG: () => png,
+          getSize: () => ({ width: 1280, height: 720 }),
+        });
+        const capturePage = vi
+          .fn<() => Promise<ReturnType<typeof pngImage>>>()
+          .mockResolvedValueOnce(pngImage(firstPng))
+          .mockResolvedValueOnce(pngImage(secondPng));
+        fromId.mockReturnValue(makeTestPreviewWebContents(capturePage));
+        yield* manager.createTab("tab_1");
+        yield* manager.registerWebview("tab_1", 42);
+        // it.effect keeps TestClock fixed until explicitly advanced.
+        const first = yield* manager.captureScreenshot("tab_1");
+        const second = yield* manager.captureScreenshot("tab_1");
+
+        expect(first.createdAt).toBe(second.createdAt);
+        expect(first.id).not.toBe(second.id);
+        expect(first.path).not.toBe(second.path);
+        expect(first.id).toMatch(/^browser-screenshot-example-com-[a-z0-9]+-[0-9a-f]{8}$/);
+        expect(second.id).toMatch(/^browser-screenshot-example-com-[a-z0-9]+-[0-9a-f]{8}$/);
+        expect(writeFile.mock.calls).toEqual([
+          [first.path, firstPng],
+          [second.path, secondPng],
+        ]);
+      }),
+    ),
+  );
+
   effectIt.effect("keeps every recorded guest unthrottled until its frame capture stops", () =>
     withManager((manager) =>
       Effect.gen(function* () {
diff --git a/apps/desktop/src/preview/Manager.ts b/apps/desktop/src/preview/Manager.ts
index bc34daee4adfa0743afa550bee9ed0cdfee2aea3..10bb0d299d3024295f792f4be5b348bb3c84fe41 100644
--- a/apps/desktop/src/preview/Manager.ts
+++ b/apps/desktop/src/preview/Manager.ts
@@ -2974,7 +2974,7 @@ const makeNativeOperations = Effect.fn("PreviewManager.makeOperations")(function
         wc,
       ),
     ]);
-    const id = `browser-screenshot-${artifactSiteSlug(wc.getURL())}-${millis.toString(36)}`;
+    const id = `browser-screenshot-${artifactSiteSlug(wc.getURL())}-${millis.toString(36)}-${NodeCrypto.randomUUID().slice(0, 8)}`;
     const artifactPath = path.join(resolvedArtifactDirectory, `${id}.png`);
     const data = image.toPNG();
     yield* fileSystem.makeDirectory(resolvedArtifactDirectory, { recursive: true }).pipe(
-- 
2.54.0