fix: use uppercase trace event phases for perfetto compatibility

Node.js's trace_events_async_hooks.js uses lowercase phase characters
('b'/'e' for NESTABLE_ASYNC_BEGIN/END) when calling V8's trace builtin.
In perfetto mode, V8's builtins-trace.cc only handles uppercase phases
('B'/'E'/'I'), causing a "Trace event phase must be a number" TypeError
that breaks utility process startup when contentTracing is active.

This was already fixed for lib/internal/http.js in the existing
build_enable_perfetto patch but trace_events_async_hooks.js was missed.

Also fixes the --trace-startup spec by removing embedded quotes from
the glob pattern argument that triggered a PERFETTO_CHECK assertion in
perfetto's NameMatchesPattern.

build/args/all.gn

@@ -2,7 +2,7 @@ is_electron_build = true
 root_extra_deps = [ "//electron" ]
 
 # Registry of NMVs --> https://github.com/nodejs/node/blob/main/doc/abi_version_registry.json
-node_module_version = 145
+node_module_version = 146
 
 v8_promise_internal_field_count = 1
 v8_embedder_string = "-electron.0"

patches/node/build_enable_perfetto.patch

@@ -63,6 +63,31 @@ index f8b4fd7c4ca5a0907806c7e804de8c951675a36a..209e3bcf8be5a23ac528dcd673bed82c
  }
  
  function ipToInt(ip) {
+diff --git a/lib/internal/trace_events_async_hooks.js b/lib/internal/trace_events_async_hooks.js
+index a9f517ffc9e4eea5bc68997ffadc85d43dde2a52..d3db6bf119a6bb9cea1d069957f89cc7f99512b7 100644
+--- a/lib/internal/trace_events_async_hooks.js
++++ b/lib/internal/trace_events_async_hooks.js
+@@ -11,15 +11,13 @@ const { trace } = internalBinding('trace_events');
+ const async_wrap = internalBinding('async_wrap');
+ const async_hooks = require('async_hooks');
+ const {
+-  CHAR_LOWERCASE_B,
+-  CHAR_LOWERCASE_E,
++  CHAR_UPPERCASE_B,
++  CHAR_UPPERCASE_E,
+ } = require('internal/constants');
+ 
+-// Use small letters such that chrome://tracing groups by the name.
+-// The behavior is not only useful but the same as the events emitted using
+-// the specific C++ macros.
+-const kBeforeEvent = CHAR_LOWERCASE_B;
+-const kEndEvent = CHAR_LOWERCASE_E;
++// See v8/src/builtins/builtins-trace.cc - must be uppercase for perfetto
++const kBeforeEvent = CHAR_UPPERCASE_B;
++const kEndEvent = CHAR_UPPERCASE_E;
+ const kTraceEventCategory = 'node,node.async_hooks';
+ 
+ const kEnabled = Symbol('enabled');
 diff --git a/node.gyp b/node.gyp
 index f5cd416b5fe7a51084bc4af9a4427a8e62599fd8..5eb70ce3820f2b82121bc102c5182ab768cbef36 100644
 --- a/node.gyp

patches/squirrel.mac/.patches

@@ -9,5 +9,5 @@ refactor_use_non-deprecated_nskeyedarchiver_apis.patch
 chore_turn_off_launchapplicationaturl_deprecation_errors_in_squirrel.patch
 fix_crash_when_process_to_extract_zip_cannot_be_launched.patch
 use_uttype_class_instead_of_deprecated_uttypeconformsto.patch
-fix_clean_up_old_staged_updates_before_downloading_new_update.patch
+fix_clean_up_orphaned_staged_updates_before_downloading_new_update.patch
 fix_add_explicit_json_property_mappings_for_shipit_request_model.patch

patches/squirrel.mac/fix_clean_up_old_staged_updates_before_downloading_new_update.patch

@@ -1,64 +0,0 @@
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: Andy Locascio <loc@anthropic.com>
-Date: Tue, 6 Jan 2026 08:23:03 -0800
-Subject: fix: clean up old staged updates before downloading new update
-
-When checkForUpdates() is called while an update is already staged,
-Squirrel creates a new temporary directory for the download without
-cleaning up the old one. This can lead to significant disk usage if
-the app keeps checking for updates without restarting.
-
-This change adds a force parameter to pruneUpdateDirectories that
-bypasses the AwaitingRelaunch state check. This is called before
-creating a new temp directory, ensuring old staged updates are
-cleaned up when a new download starts.
-
-diff --git a/Squirrel/SQRLUpdater.m b/Squirrel/SQRLUpdater.m
-index d156616e81e6f25a3bded30e6216b8fc311f31bc..6cd4346bf43b191147aff819cb93387e71275a46 100644
---- a/Squirrel/SQRLUpdater.m
-+++ b/Squirrel/SQRLUpdater.m
-@@ -543,11 +543,17 @@ - (RACSignal *)downloadBundleForUpdate:(SQRLUpdate *)update intoDirectory:(NSURL
- #pragma mark File Management
- 
- - (RACSignal *)uniqueTemporaryDirectoryForUpdate {
--	return [[[RACSignal
-+	// Clean up any old staged update directories before creating a new one.
-+	// This prevents disk usage from growing when checkForUpdates() is called
-+	// multiple times without the app restarting.
-+	return [[[[[self
-+		pruneUpdateDirectoriesWithForce:YES]
-+		ignoreValues]
-+		concat:[RACSignal
- 		defer:^{
- 			SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:SQRLShipItLauncher.shipItJobLabel];
- 			return [directoryManager storageURL];
--		}]
-+		}]]
- 		flattenMap:^(NSURL *storageURL) {
- 			NSURL *updateDirectoryTemplate = [storageURL URLByAppendingPathComponent:[SQRLUpdaterUniqueTemporaryDirectoryPrefix stringByAppendingString:@"XXXXXXX"]];
- 			char *updateDirectoryCString = strdup(updateDirectoryTemplate.path.fileSystemRepresentation);
-@@ -643,7 +649,7 @@ - (BOOL)isRunningOnReadOnlyVolume {
- 
- - (RACSignal *)performHousekeeping {
- 	return [[RACSignal
--		merge:@[ [self pruneUpdateDirectories], [self truncateLogs] ]]
-+		merge:@[ [self pruneUpdateDirectoriesWithForce:NO], [self truncateLogs] ]]
- 		catch:^(NSError *error) {
- 			NSLog(@"Error doing housekeeping: %@", error);
- 			return [RACSignal empty];
-@@ -658,11 +664,12 @@ - (RACSignal *)performHousekeeping {
- ///
- /// Sends each removed directory then completes, or errors, on an unspecified
- /// thread.
--- (RACSignal *)pruneUpdateDirectories {
-+- (RACSignal *)pruneUpdateDirectoriesWithForce:(BOOL)force {
- 	return [[[RACSignal
- 		defer:^{
--			// If we already have updates downloaded we don't wanna prune them.
--			if (self.state == SQRLUpdaterStateAwaitingRelaunch) return [RACSignal empty];
-+			// If we already have updates downloaded we don't wanna prune them,
-+			// unless force is YES (used when starting a new download).
-+			if (!force && self.state == SQRLUpdaterStateAwaitingRelaunch) return [RACSignal empty];
- 
- 			SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:SQRLShipItLauncher.shipItJobLabel];
- 			return [directoryManager storageURL];

patches/squirrel.mac/fix_clean_up_orphaned_staged_updates_before_downloading_new_update.patch

@@ -0,0 +1,130 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Andy Locascio <loc@anthropic.com>
+Date: Tue, 6 Jan 2026 08:23:03 -0800
+Subject: fix: clean up orphaned staged updates before downloading new update
+
+When checkForUpdates() is called while an update is already staged,
+Squirrel creates a new temporary directory for the download without
+cleaning up the old one. This can lead to significant disk usage if
+the app keeps checking for updates without restarting.
+
+This change adds a pruneOrphanedUpdateDirectories step before creating
+a new temp directory. Unlike a blanket prune, this reads the current
+ShipItState.plist and preserves the directory it references, deleting
+only truly orphaned update directories. This keeps the on-disk
+footprint bounded (at most 2 dirs) while ensuring quitAndInstall
+remains safe to call even when a new check is in progress.
+
+Refs https://github.com/electron/electron/issues/50200
+
+diff --git a/Squirrel/SQRLUpdater.m b/Squirrel/SQRLUpdater.m
+index d156616e81e6f25a3bded30e6216b8fc311f31bc..41856e5754228d33982db72f97f2ff241615a357 100644
+--- a/Squirrel/SQRLUpdater.m
++++ b/Squirrel/SQRLUpdater.m
+@@ -543,11 +543,19 @@ - (RACSignal *)downloadBundleForUpdate:(SQRLUpdate *)update intoDirectory:(NSURL
+ #pragma mark File Management
+ 
+ - (RACSignal *)uniqueTemporaryDirectoryForUpdate {
+-	return [[[RACSignal
++	// Clean up any orphaned update directories before creating a new one.
++	// This prevents disk usage from growing when checkForUpdates() is called
++	// multiple times without the app restarting. The currently staged update
++	// (referenced by ShipItState.plist) is always preserved so quitAndInstall
++	// remains safe to call while a new check is in progress.
++	return [[[[[self
++		pruneOrphanedUpdateDirectories]
++		ignoreValues]
++		concat:[RACSignal
+ 		defer:^{
+ 			SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:SQRLShipItLauncher.shipItJobLabel];
+ 			return [directoryManager storageURL];
+-		}]
++		}]]
+ 		flattenMap:^(NSURL *storageURL) {
+ 			NSURL *updateDirectoryTemplate = [storageURL URLByAppendingPathComponent:[SQRLUpdaterUniqueTemporaryDirectoryPrefix stringByAppendingString:@"XXXXXXX"]];
+ 			char *updateDirectoryCString = strdup(updateDirectoryTemplate.path.fileSystemRepresentation);
+@@ -668,25 +676,68 @@ - (RACSignal *)pruneUpdateDirectories {
+ 			return [directoryManager storageURL];
+ 		}]
+ 		flattenMap:^(NSURL *storageURL) {
+-			NSFileManager *manager = [[NSFileManager alloc] init];
+-			NSDirectoryEnumerator *enumerator = [manager enumeratorAtURL:storageURL includingPropertiesForKeys:nil options:NSDirectoryEnumerationSkipsSubdirectoryDescendants errorHandler:^(NSURL *URL, NSError *error) {
+-				NSLog(@"Error enumerating item %@ within directory %@: %@", URL, storageURL, error);
+-				return YES;
+-			}];
++			return [self removeUpdateDirectoriesInStorageURL:storageURL excludingURL:nil];
++		}]
++		setNameWithFormat:@"%@ -prunedUpdateDirectories", self];
++}
+ 
+-			return [[enumerator.rac_sequence.signal
+-				filter:^(NSURL *enumeratedURL) {
+-					NSString *name = enumeratedURL.lastPathComponent;
+-					return [name hasPrefix:SQRLUpdaterUniqueTemporaryDirectoryPrefix];
+-				}]
+-				doNext:^(NSURL *directoryURL) {
+-					NSError *error = nil;
+-					if (![manager removeItemAtURL:directoryURL error:&error]) {
+-						NSLog(@"Error removing old update directory at %@: %@", directoryURL, error.sqrl_verboseDescription);
+-					}
++/// Lazily removes orphaned temporary directories upon subscription, always
++/// preserving the directory currently referenced by ShipItState.plist so that
++/// quitAndInstall remains safe to call mid-check.
++///
++/// Safe to call in any state. Sends each removed directory then completes on
++/// an unspecified thread. Errors reading the staged request are swallowed
++/// (treated as "nothing staged").
++- (RACSignal *)pruneOrphanedUpdateDirectories {
++	return [[[[[SQRLShipItRequest
++		readUsingURL:self.shipItStateURL]
++		map:^(SQRLShipItRequest *request) {
++			// The request holds the URL to the staged .app bundle; its parent
++			// is the update.XXXXXXX directory we must preserve.
++			return [request.updateBundleURL URLByDeletingLastPathComponent];
++		}]
++		catch:^(NSError *error) {
++			// No staged request (or unreadable) — nothing to preserve.
++			return [RACSignal return:nil];
++		}]
++		flattenMap:^(NSURL *stagedDirectoryURL) {
++			SQRLDirectoryManager *directoryManager = [[SQRLDirectoryManager alloc] initWithApplicationIdentifier:SQRLShipItLauncher.shipItJobLabel];
++			return [[directoryManager storageURL]
++				flattenMap:^(NSURL *storageURL) {
++					return [self removeUpdateDirectoriesInStorageURL:storageURL excludingURL:stagedDirectoryURL];
+ 				}];
+ 		}]
+-		setNameWithFormat:@"%@ -prunedUpdateDirectories", self];
++		setNameWithFormat:@"%@ -pruneOrphanedUpdateDirectories", self];
++}
++
++/// Shared enumerate-and-delete logic for update temp directories.
++///
++/// storageURL  - The Squirrel storage root to enumerate. Must not be nil.
++/// excludedURL - Directory to skip (compared by standardized path). May be nil.
++- (RACSignal *)removeUpdateDirectoriesInStorageURL:(NSURL *)storageURL excludingURL:(NSURL *)excludedURL {
++	NSParameterAssert(storageURL != nil);
++
++	NSFileManager *manager = [[NSFileManager alloc] init];
++	NSDirectoryEnumerator *enumerator = [manager enumeratorAtURL:storageURL includingPropertiesForKeys:nil options:NSDirectoryEnumerationSkipsSubdirectoryDescendants errorHandler:^(NSURL *URL, NSError *error) {
++		NSLog(@"Error enumerating item %@ within directory %@: %@", URL, storageURL, error);
++		return YES;
++	}];
++
++	NSString *excludedPath = excludedURL.URLByStandardizingPath.path;
++
++	return [[enumerator.rac_sequence.signal
++		filter:^(NSURL *enumeratedURL) {
++			NSString *name = enumeratedURL.lastPathComponent;
++			if (![name hasPrefix:SQRLUpdaterUniqueTemporaryDirectoryPrefix]) return NO;
++			if (excludedPath != nil && [enumeratedURL.URLByStandardizingPath.path isEqualToString:excludedPath]) return NO;
++			return YES;
++		}]
++		doNext:^(NSURL *directoryURL) {
++			NSError *error = nil;
++			if (![manager removeItemAtURL:directoryURL error:&error]) {
++				NSLog(@"Error removing old update directory at %@: %@", directoryURL, error.sqrl_verboseDescription);
++			}
++		}];
+ }
+ 
+ 

spec/api-autoupdater-darwin-spec.ts

@@ -403,7 +403,7 @@ ifdescribe(shouldRunCodesignTests)('autoUpdater behavior', function () {
       });
     });
 
-    it('should clean up old staged update directories when a new update is downloaded', async () => {
+    it('should preserve the staged update directory and prune orphaned ones when a new update is downloaded', async () => {
       // Clean up any existing update directories before the test
       await cleanSquirrelCache();
 
@@ -419,16 +419,23 @@ ifdescribe(shouldRunCodesignTests)('autoUpdater behavior', function () {
         }, async (_, updateZipPath3) => {
           let updateCount = 0;
           let downloadCount = 0;
-          let directoriesDuringSecondDownload: string[] = [];
+          let dirsDuringFirstDownload: string[] = [];
+          let dirsDuringSecondDownload: string[] = [];
 
           server.get('/update-file', async (req, res) => {
             downloadCount++;
-            // When the second download request arrives, Squirrel has already
-            // called uniqueTemporaryDirectoryForUpdate which (with our patch)
-            // cleans up old directories before creating the new one.
-            // Without the patch, both directories would exist at this point.
-            if (downloadCount === 2) {
-              directoriesDuringSecondDownload = await getUpdateDirectoriesInCache();
+            // Snapshot update directories at the moment each download begins.
+            // By this point uniqueTemporaryDirectoryForUpdate has already run
+            // (prune + mkdtemp). We want to verify:
+            //   1st download: 1 dir (nothing to preserve, nothing to prune)
+            //   2nd download: 2 dirs (staged dir from 1st check is preserved
+            //                 so quitAndInstall stays safe, + new temp dir)
+            // The count never exceeds 2 across repeated checks — orphaned dirs
+            // (no longer referenced by ShipItState.plist) get pruned.
+            if (downloadCount === 1) {
+              dirsDuringFirstDownload = await getUpdateDirectoriesInCache();
+            } else if (downloadCount === 2) {
+              dirsDuringSecondDownload = await getUpdateDirectoriesInCache();
             }
             res.download(updateCount > 1 ? updateZipPath3 : updateZipPath2);
           });
@@ -455,15 +462,181 @@ ifdescribe(shouldRunCodesignTests)('autoUpdater behavior', function () {
 
           await relaunchPromise;
 
-          // During the second download, the old staged update directory should
-          // have been cleaned up. With our patch, there should be exactly 1
-          // directory (the new one). Without the patch, there would be 2.
-          expect(directoriesDuringSecondDownload).to.have.lengthOf(1,
-            `Expected 1 update directory during second download but found ${directoriesDuringSecondDownload.length}: ${directoriesDuringSecondDownload.join(', ')}`);
+          // First download: exactly one temp dir (the first update).
+          expect(dirsDuringFirstDownload).to.have.lengthOf(1,
+            `Expected 1 update directory during first download but found ${dirsDuringFirstDownload.length}: ${dirsDuringFirstDownload.join(', ')}`);
+
+          // Second download: exactly two — the staged one preserved + the new
+          // one. Crucially the first download's directory must still be present,
+          // otherwise a mid-download quitAndInstall would find a dangling
+          // ShipItState.plist.
+          expect(dirsDuringSecondDownload).to.have.lengthOf(2,
+            `Expected 2 update directories during second download (staged + new) but found ${dirsDuringSecondDownload.length}: ${dirsDuringSecondDownload.join(', ')}`);
+          expect(dirsDuringSecondDownload).to.include(dirsDuringFirstDownload[0],
+            'The staged update directory from the first download must be preserved during the second download');
         });
       });
     });
 
+    it('should keep the update directory count bounded across repeated checks', async () => {
+      // Verifies the orphan prune actually fires: after a second download
+      // completes and rewrites ShipItState.plist, the first directory is no
+      // longer referenced and must be removed when a third check begins.
+      // Without this, directories would accumulate forever.
+      await cleanSquirrelCache();
+
+      await withUpdatableApp({
+        nextVersion: '2.0.0',
+        startFixture: 'update-triple-stack',
+        endFixture: 'update-triple-stack'
+      }, async (appPath, updateZipPath2) => {
+        await withUpdatableApp({
+          nextVersion: '3.0.0',
+          startFixture: 'update-triple-stack',
+          endFixture: 'update-triple-stack'
+        }, async (_, updateZipPath3) => {
+          await withUpdatableApp({
+            nextVersion: '4.0.0',
+            startFixture: 'update-triple-stack',
+            endFixture: 'update-triple-stack'
+          }, async (__, updateZipPath4) => {
+            let downloadCount = 0;
+            const dirsPerDownload: string[][] = [];
+
+            server.get('/update-file', async (req, res) => {
+              downloadCount++;
+              // Snapshot after prune+mkdtemp but before the payload transfers.
+              dirsPerDownload.push(await getUpdateDirectoriesInCache());
+              const zips = [updateZipPath2, updateZipPath3, updateZipPath4];
+              res.download(zips[Math.min(downloadCount, zips.length) - 1]);
+            });
+            server.get('/update-check', (req, res) => {
+              res.json({
+                url: `http://localhost:${port}/update-file`,
+                name: 'My Release Name',
+                notes: 'Theses are some release notes innit',
+                pub_date: (new Date()).toString()
+              });
+            });
+            const relaunchPromise = new Promise<void>((resolve) => {
+              server.get('/update-check/updated/:version', (req, res) => {
+                res.status(204).send();
+                resolve();
+              });
+            });
+
+            const launchResult = await launchApp(appPath, [`http://localhost:${port}/update-check`]);
+            logOnError(launchResult, () => {
+              expect(launchResult).to.have.property('code', 0);
+              expect(launchResult.out).to.include('Update Downloaded');
+            });
+
+            await relaunchPromise;
+            expect(requests[requests.length - 1].url).to.equal('/update-check/updated/4.0.0');
+
+            expect(dirsPerDownload).to.have.lengthOf(3);
+
+            // 1st: fresh cache, 1 dir.
+            expect(dirsPerDownload[0]).to.have.lengthOf(1,
+              `1st download: ${dirsPerDownload[0].join(', ')}`);
+
+            // 2nd: staged (1st) preserved + new = 2 dirs.
+            expect(dirsPerDownload[1]).to.have.lengthOf(2,
+              `2nd download: ${dirsPerDownload[1].join(', ')}`);
+            expect(dirsPerDownload[1]).to.include(dirsPerDownload[0][0]);
+
+            // 3rd: 1st is now orphaned (plist points to 2nd) — must be pruned.
+            // Staged (2nd) preserved + new = still 2 dirs. Bounded.
+            expect(dirsPerDownload[2]).to.have.lengthOf(2,
+              `3rd download: ${dirsPerDownload[2].join(', ')}`);
+            expect(dirsPerDownload[2]).to.not.include(dirsPerDownload[0][0],
+              'The first (now orphaned) update directory must be pruned on the third check');
+            const secondDir = dirsPerDownload[1].find(d => d !== dirsPerDownload[0][0]);
+            expect(dirsPerDownload[2]).to.include(secondDir,
+              'The second (currently staged) update directory must be preserved on the third check');
+          });
+        });
+      });
+    });
+
+    // Regression test for https://github.com/electron/electron/issues/50200
+    //
+    // When checkForUpdates() is called again after an update has been staged,
+    // Squirrel creates a new temporary directory and prunes old ones. If the
+    // prune removes the directory that ShipItState.plist references while the
+    // second download is still in flight, a subsequent quitAndInstall() will
+    // fail with ENOENT and the app will never relaunch.
+    it('should install the staged update when quitAndInstall is called while a second check is in flight', async () => {
+      await cleanSquirrelCache();
+
+      await withUpdatableApp({
+        nextVersion: '2.0.0',
+        startFixture: 'update-race',
+        endFixture: 'update-race'
+      }, async (appPath, updateZipPath) => {
+        let downloadCount = 0;
+        let stalledResponse: express.Response | null = null;
+
+        server.get('/update-file', (req, res) => {
+          downloadCount++;
+          if (downloadCount === 1) {
+            // First download completes normally and stages the update.
+            res.download(updateZipPath);
+          } else {
+            // Second download: stall indefinitely to simulate a slow
+            // network. This keeps the second check "in progress" when
+            // quitAndInstall() fires. Hold onto the response so we can
+            // clean it up later.
+            stalledResponse = res;
+          }
+        });
+        server.get('/update-check', (req, res) => {
+          res.json({
+            url: `http://localhost:${port}/update-file`,
+            name: 'My Release Name',
+            notes: 'Theses are some release notes innit',
+            pub_date: (new Date()).toString()
+          });
+        });
+        const relaunchPromise = new Promise<void>((resolve) => {
+          server.get('/update-check/updated/:version', (req, res) => {
+            res.status(204).send();
+            resolve();
+          });
+        });
+
+        const launchResult = await launchApp(appPath, [`http://localhost:${port}/update-check`]);
+        logOnError(launchResult, () => {
+          expect(launchResult).to.have.property('code', 0);
+          expect(launchResult.out).to.include('Update Downloaded');
+          expect(launchResult.out).to.include('Calling quitAndInstall mid-download');
+          // First check + first download + second check + stalled second download.
+          expect(requests).to.have.lengthOf(4);
+          expect(requests[0]).to.have.property('url', '/update-check');
+          expect(requests[1]).to.have.property('url', '/update-file');
+          expect(requests[2]).to.have.property('url', '/update-check');
+          expect(requests[3]).to.have.property('url', '/update-file');
+          // The second download must have been in flight (never completed)
+          // when quitAndInstall was called.
+          expect(launchResult.out).to.not.include('Unexpected second download completion');
+        });
+
+        // Unblock the stalled response now that the initial app has exited
+        // so the express server can shut down cleanly.
+        if (stalledResponse) {
+          (stalledResponse as express.Response).status(500).end();
+        }
+
+        // The originally staged update (2.0.0) must have been applied and
+        // the app must relaunch, proving the staged update directory was
+        // not pruned out from under ShipItState.plist.
+        await relaunchPromise;
+        expect(requests).to.have.lengthOf(5);
+        expect(requests[4].url).to.equal('/update-check/updated/2.0.0');
+        expect(requests[4].header('user-agent')).to.include('Electron/');
+      });
+    });
+
     it('should update to lower version numbers', async () => {
       await withUpdatableApp({
         nextVersion: '0.0.1',

spec/chromium-spec.ts

@@ -567,14 +567,7 @@ describe('command line switches', () => {
     });
 
     it('creates startup trace', async () => {
-      // node.async_hooks relies on %trace builtin to log trace points from JS
-      // https://github.com/nodejs/node/blob/8b199eef3dd4de910a6521adc42ae611a62a19e1/lib/internal/trace_events_async_hooks.js#L48-L53
-      // The phase event arg TRACE_EVENT_PHASE_NESTABLE_ASYNC_(BEGIN | END) is not supported in v8_use_perfetto mode
-      // https://source.chromium.org/chromium/chromium/src/+/main:v8/src/builtins/builtins-trace.cc;l=201-216
-      // and leads to the following error: TypeError: Trace event phase must be a number.
-      // TODO: Identify why the error started appearing with roll https://github.com/electron/electron/pull/47561
-      // given both v8_use_perfetto has been enabled before the roll and builtins-trace macro hasn't changed.
-      const rc = await startRemoteControlApp(['--trace-startup="*,-node.async_hooks"', `--trace-startup-file=${outputFilePath}`, '--trace-startup-duration=1', '--enable-logging']);
+      const rc = await startRemoteControlApp(['--trace-startup=*', `--trace-startup-file=${outputFilePath}`, '--trace-startup-duration=1', '--enable-logging']);
       const stderrComplete = new Promise<string>(resolve => {
         let stderr = '';
         rc.process.stderr!.on('data', (chunk) => {

spec/fixtures/auto-update/update-race/index.js

@@ -0,0 +1,82 @@
+const { app, autoUpdater } = require('electron');
+
+const fs = require('node:fs');
+const path = require('node:path');
+
+process.on('uncaughtException', (err) => {
+  console.error(err);
+  process.exit(1);
+});
+
+let installInvoked = false;
+
+autoUpdater.on('error', (err) => {
+  // Once quitAndInstall() has been invoked the second in-flight check may
+  // surface a cancellation/network error as the process tears down; ignore
+  // errors after that point so we test the actual install race, not teardown.
+  if (installInvoked) {
+    console.log('Ignoring post-install error:', err && err.message);
+    return;
+  }
+  console.error(err);
+  process.exit(1);
+});
+
+const urlPath = path.resolve(__dirname, '../../../../url.txt');
+let feedUrl = process.argv[1];
+
+if (feedUrl === 'remain-open') {
+  // Hold the event loop
+  setInterval(() => {});
+} else {
+  if (!feedUrl || !feedUrl.startsWith('http')) {
+    feedUrl = `${fs.readFileSync(urlPath, 'utf8')}/${app.getVersion()}`;
+  } else {
+    fs.writeFileSync(urlPath, `${feedUrl}/updated`);
+  }
+
+  autoUpdater.setFeedURL({
+    url: feedUrl
+  });
+
+  autoUpdater.checkForUpdates();
+
+  autoUpdater.on('update-available', () => {
+    console.log('Update Available');
+  });
+
+  let downloadedOnce = false;
+
+  autoUpdater.on('update-downloaded', () => {
+    console.log('Update Downloaded');
+    if (!downloadedOnce) {
+      downloadedOnce = true;
+      // Simulate a periodic update check firing after an update was already
+      // staged. The test server is expected to stall this second download so
+      // that it remains in flight while we call quitAndInstall().
+      // The short delay lets checkForUpdatesCommand's RACCommand executing
+      // state settle; calling immediately would hit the command's "disabled"
+      // guard since RACCommand disallows concurrent execution.
+      setTimeout(() => {
+        autoUpdater.checkForUpdates();
+        // Give Squirrel enough time to enter the second check (creating a new
+        // temporary directory, which with the regression prunes the directory
+        // that the staged update lives in) before invoking the install.
+        setTimeout(() => {
+          console.log('Calling quitAndInstall mid-download');
+          installInvoked = true;
+          autoUpdater.quitAndInstall();
+        }, 3000);
+      }, 1000);
+    } else {
+      // Should not reach here — the second download is stalled on purpose.
+      console.log('Unexpected second download completion');
+      autoUpdater.quitAndInstall();
+    }
+  });
+
+  autoUpdater.on('update-not-available', () => {
+    console.error('No update available');
+    process.exit(1);
+  });
+}

spec/fixtures/auto-update/update-race/package.json

@@ -0,0 +1,5 @@
+{
+  "name": "electron-test-update-race",
+  "version": "1.0.0",
+  "main": "./index.js"
+}

spec/fixtures/auto-update/update-triple-stack/index.js

@@ -0,0 +1,57 @@
+const { app, autoUpdater } = require('electron');
+
+const fs = require('node:fs');
+const path = require('node:path');
+
+process.on('uncaughtException', (err) => {
+  console.error(err);
+  process.exit(1);
+});
+
+autoUpdater.on('error', (err) => {
+  console.error(err);
+  process.exit(1);
+});
+
+const urlPath = path.resolve(__dirname, '../../../../url.txt');
+let feedUrl = process.argv[1];
+
+if (feedUrl === 'remain-open') {
+  // Hold the event loop
+  setInterval(() => {});
+} else {
+  if (!feedUrl || !feedUrl.startsWith('http')) {
+    feedUrl = `${fs.readFileSync(urlPath, 'utf8')}/${app.getVersion()}`;
+  } else {
+    fs.writeFileSync(urlPath, `${feedUrl}/updated`);
+  }
+
+  autoUpdater.setFeedURL({
+    url: feedUrl
+  });
+
+  autoUpdater.checkForUpdates();
+
+  autoUpdater.on('update-available', () => {
+    console.log('Update Available');
+  });
+
+  let updateStackCount = 0;
+
+  autoUpdater.on('update-downloaded', () => {
+    updateStackCount++;
+    console.log('Update Downloaded');
+    if (updateStackCount > 2) {
+      autoUpdater.quitAndInstall();
+    } else {
+      setTimeout(() => {
+        autoUpdater.checkForUpdates();
+      }, 1000);
+    }
+  });
+
+  autoUpdater.on('update-not-available', () => {
+    console.error('No update available');
+    process.exit(1);
+  });
+}

spec/fixtures/auto-update/update-triple-stack/package.json

@@ -0,0 +1,5 @@
+{
+  "name": "electron-test-update-triple-stack",
+  "version": "1.0.0",
+  "main": "./index.js"
+}