executeFrontendSubRequest() clear my loaded plugin action in $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['extbase']['extensions']

[Apen]

What are you trying to achieve?

Use executeFrontendSubRequest() to test some plugin rendering.

How to reproduce the issue?

I my extension, i execute some tests and i load some extension like this

protected array $testExtensionsToLoad = [
        'sng/sngpackage',
        __DIR__ . '/../Fixtures/Extensions/sngpackagedemo',
    ];

My plugin in "sngpackagedemo" is correctly initialized, and in my test class, i can check that $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['extbase']['extensions'] contain the description of my plugin and action.

If i use executeFrontendSubRequest() , i have an error like InvalidArgumentException: The default controller for extension "Sngpackagedemo" and plugin "xxx" can not be determined. Please check for TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin() in your ext_localconf.php.

After some research i find the problem in this function and its when bootstrapping in :

$container = Bootstrap::init(ClassLoadingInformation::getClassLoader());

If i debug before init() my extension is in $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['extbase']['extensions'].
If i debug after, i lose my plugin description in $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['extbase']['extensions'].

If i do something like this in the code :

$save = $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['extbase']['extensions'];
$container = Bootstrap::init(ClassLoadingInformation::getClassLoader());
$GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['extbase']['extensions'] = $save;

Everything is working. This is ugly, but its only for testing purpose.

Another thing i test is forcing the declaration :

protected array $configurationToUseInTestInstance = [
        'FE' => [
            'cacheHash' => [
                'enforceValidation' => false,
            ],
        ],
        'EXTCONF' => [
            'extbase' => [
                'extensions' => [
                    'Sngpackagedemo' => [
                        'plugins' => [
                            'Displayusers' => [
                                'controllers' => [
                                    'Sng\Sngpackagedemo\Controller\FrontendUserController' => [
                                        'className' => 'Sng\Sngpackagedemo\Controller\FrontendUserController',
                                        'alias' => 'FrontendUser',
                                        'actions' => [
                                            'list',
                                        ],
                                        'nonCacheableActions' => [
                                            'list',
                                        ],
                                    ],
                                ],
                                'pluginType' => 'CType',
                            ],
                        ],
                    ],
                ],
            ],
        ],
    ];

With this code it works perfectly. But it seems strange to me :-)

Is there anything i miss? Why the new Bootstrap::init() doesn't read or execute the configurePlugin() in my custom extension ? I debug the code and everything are loaded in this request.

Additional information you would like to provide?

Composer
PHP : 8.4
TYPO3 : 13.4.19
typo3/testing-framework : 9.2.0