diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fbef6d65106..f13687729ce 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -252,7 +252,7 @@ jobs:
         with:
           java-version: 1.8
 
-      - name: Run regular unit tests with unscoped PHAR
+      - name: Run regular test suite with unscoped PHAR
         run: ant run-regular-tests-with-unscoped-phar
 
       - name: Run PHAR-specific end-to-end tests with scoped PHAR
diff --git a/build.xml b/build.xml
index 7a07d351d9b..db428a1f685 100644
--- a/build.xml
+++ b/build.xml
@@ -454,6 +454,7 @@
             <arg value="--output" />
             <arg path="${basedir}/tests/autoload.php" />
             <arg path="${basedir}/tests/_files" />
+            <arg path="${basedir}/tests/end-to-end/_files" />
             <arg path="${basedir}/tests/end-to-end/execution-order/_files" />
             <arg path="${basedir}/tests/unit" />
         </exec>
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index 1316a2141ba..09e4fbed085 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -9,25 +9,32 @@
  */
 const TEST_FILES_PATH = __DIR__ . DIRECTORY_SEPARATOR . '_files' . DIRECTORY_SEPARATOR;
 
-if (file_exists(__DIR__ . '/../vendor/autoload.php') && file_exists(__DIR__ . '/autoload.php')) {
-    print 'More than one test fixture autoloader is available, exiting.' . \PHP_EOL;
+$composer = file_exists(__DIR__ . '/../vendor/autoload.php');
+$phar     = file_exists(__DIR__ . '/autoload.php');
+
+if ($composer && $phar) {
+    print 'More than one test fixture autoloader is available, exiting.' . PHP_EOL;
+
+    exit(1);
+}
+
+if (!$composer && !$phar) {
+    print 'No test fixture autoloader was registered, exiting.' . PHP_EOL;
 
     exit(1);
 }
 
-if (file_exists(__DIR__ . '/../vendor/autoload.php')) {
+if ($composer) {
     if (!defined('PHPUNIT_COMPOSER_INSTALL')) {
         define('PHPUNIT_COMPOSER_INSTALL', dirname(__DIR__) . '/vendor/autoload.php');
     }
 
     require_once __DIR__ . '/../vendor/autoload.php';
-
-    return;
 }
 
-if (file_exists(__DIR__ . '/autoload.php')) {
+if ($phar) {
     if (!defined('__PHPUNIT_PHAR__')) {
-        define('__PHPUNIT_PHAR__', realpath($_SERVER['_']));
+        require_once __DIR__ . '/../build/artifacts/phpunit-snapshot.phar';
     }
 
     require_once __DIR__ . '/autoload.php';
@@ -38,12 +45,6 @@
     foreach (json_decode(file_get_contents($jsonFile), true)['autoload-dev']['files'] as $file) {
         require_once $base . DIRECTORY_SEPARATOR . $file;
     }
-
-    unset($jsonFile, $base, $file);
-
-    return;
 }
 
-print 'No test fixture autoloader was registered, exiting.' . \PHP_EOL;
-
-exit(1);
+unset($composer, $phar, $jsonFile, $base, $file);
diff --git a/tests/end-to-end/regression/GitHub/1351.phpt b/tests/end-to-end/regression/GitHub/1351.phpt
deleted file mode 100644
index b8cc78ab5b6..00000000000
--- a/tests/end-to-end/regression/GitHub/1351.phpt
+++ /dev/null
@@ -1,45 +0,0 @@
---TEST--
-https://github.com/sebastianbergmann/phpunit/issues/1351
---SKIPIF--
-<?php declare(strict_types=1);
-if (!extension_loaded('pdo') || !in_array('sqlite', PDO::getAvailableDrivers())) {
-    print 'skip: PDO_SQLITE is required';
-}
---FILE--
-<?php declare(strict_types=1);
-$_SERVER['argv'][] = '--do-not-cache-result';
-$_SERVER['argv'][] = '--no-configuration';
-$_SERVER['argv'][] = '--process-isolation';
-$_SERVER['argv'][] = __DIR__ . '/1351/Issue1351Test.php';
-
-require_once __DIR__ . '/../../../bootstrap.php';
-PHPUnit\TextUI\Command::main();
---EXPECTF--
-PHPUnit %s by Sebastian Bergmann and contributors.
-
-F.E.E                                                               5 / 5 (100%)
-
-Time: %s, Memory: %s
-
-There were 2 errors:
-
-1) Issue1351Test::testExceptionPre
-RuntimeException: Expected rethrown exception.
-%A
-Caused by
-LogicException: Expected exception.
-%A
-
-2) Issue1351Test::testPhpCoreLanguageException
-PDOException: SQLSTATE[HY000]: General error: 1 no such table: php_wtf
-%A
-
---
-
-There was 1 failure:
-
-1) Issue1351Test::testFailurePre
-Expected failure.
-%A
-ERRORS!
-Tests: 5, Assertions: 5, Errors: 2, Failures: 1.
diff --git a/tests/end-to-end/regression/GitHub/1351/ChildProcessClass1351.php b/tests/end-to-end/regression/GitHub/1351/ChildProcessClass1351.php
deleted file mode 100644
index 27121210ae2..00000000000
--- a/tests/end-to-end/regression/GitHub/1351/ChildProcessClass1351.php
+++ /dev/null
@@ -1,12 +0,0 @@
-<?php declare(strict_types=1);
-/*
- * This file is part of PHPUnit.
- *
- * (c) Sebastian Bergmann <sebastian@phpunit.de>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-class ChildProcessClass1351
-{
-}
diff --git a/tests/end-to-end/regression/GitHub/1351/Issue1351Test.php b/tests/end-to-end/regression/GitHub/1351/Issue1351Test.php
deleted file mode 100644
index f411aa1bac1..00000000000
--- a/tests/end-to-end/regression/GitHub/1351/Issue1351Test.php
+++ /dev/null
@@ -1,59 +0,0 @@
-<?php declare(strict_types=1);
-/*
- * This file is part of PHPUnit.
- *
- * (c) Sebastian Bergmann <sebastian@phpunit.de>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-use PHPUnit\Framework\TestCase;
-
-class Issue1351Test extends TestCase
-{
-    protected $instance;
-
-    /**
-     * @runInSeparateProcess
-     */
-    public function testFailurePre(): void
-    {
-        $this->instance = new ChildProcessClass1351;
-        $this->assertFalse(true, 'Expected failure.');
-    }
-
-    public function testFailurePost(): void
-    {
-        $this->assertNull($this->instance);
-        $this->assertFalse(\class_exists(ChildProcessClass1351::class, false), 'ChildProcessClass1351 is not loaded.');
-    }
-
-    /**
-     * @runInSeparateProcess
-     */
-    public function testExceptionPre(): void
-    {
-        $this->instance = new ChildProcessClass1351;
-
-        try {
-            throw new LogicException('Expected exception.');
-        } catch (LogicException $e) {
-            throw new RuntimeException('Expected rethrown exception.', 0, $e);
-        }
-    }
-
-    public function testExceptionPost(): void
-    {
-        $this->assertNull($this->instance);
-        $this->assertFalse(\class_exists(ChildProcessClass1351::class, false), 'ChildProcessClass1351 is not loaded.');
-    }
-
-    public function testPhpCoreLanguageException(): void
-    {
-        // User-space code cannot instantiate a PDOException with a string code,
-        // so trigger a real one.
-        $connection = new PDO('sqlite::memory:');
-        $connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
-        $connection->query("DELETE FROM php_wtf WHERE exception_code = 'STRING'");
-    }
-}