Complete Error:

Fatal error: Uncaught TypeError: Argument 1 passed to TYPO3\CMS\Frontend\Http\Application::__construct() must be an instance of TYPO3\CMS\Core\Configuration\ConfigurationManager, instance of Composer\Autoload\ClassLoader given, called in /folder/domain.de/index.php on line 33 and defined in /folder/typo3_src-9.5.9/typo3/sysext/frontend/Classes/Http/Application.php:54 Stack trace: #0 /folder/domain.de/index.php(33): TYPO3\CMS\Frontend\Http\Application->__construct(Object(Composer\Autoload\ClassLoader)) #1 /folder/domain.de/index.php(34): {closure}() #2 {main} thrown in /folder/typo3_src-9.5.9/typo3/sysext/frontend/Classes/Http/Application.php on line 54

• Type: Migration: TYPO3 7.6.31 over 8.7.27 to 9.5.9
• PHP Version: 7.2
• mySQL Version: 5.6.19

Reproduction:

TYPO3 7.6.31¶

• Set page.config.contentObjectExceptionHandler = 0 in Typoscript
• Removing

• direct_mail_subscription
• sr_feuser_register
• direct_mail
• JumpURL
• RealURL
• Cal
• Tt_address
• Static info tables

• Install Tool > DB Cleanup
• Upgrade to actual given version:

• Powermail
• Gridelements

• Install Tool > Upgrade wizward

• Set the "Files:replace" permission for all BE user/groups with "Files:write" set
• Update module access to file list module

• typo3_src to ../typo3_src-8.7.27
• typo3 to typo3_src/typo3
• vendor to typo3_src/vendor
• index.php is copied, because in my provider I need to do this.

TYPO3 8.7.27¶

• Install Tool
• Upgrade wizard

• Set the "Files:replace" permission for all BE user/groups with "Files:write" set
• Migrate the Flexform for CType "table" to regular fields in tt_content
• Update module access to file list module
• Move "wizard done" flags from LocalConfiguration.php to system registry
• Migrate all file relations from fe_users.image to sys_file_references
• Execute database migrations on single rows
• Remove unneeded CLI backend users
• Fill translation source field (l10n_source)
• Migrate "css_styled_content" static template location
• [Optional] Migrate upload content element rendering from layout to uploads_type
• Migrate file references that are stored in a wrong way to correct scheme
• Update sorting of sys_language records

• Database compare
• Deleting realurl_config.php in typo3conf
• Update Extensions:

• Gridelememts
• Powermail

• Checking website whether its running
• Removing static Template in Typoscript: Css_styled content

• typo3_src to ../typo3_src-9.5.9
• typo3 to typo3_src/typo3
• vendor to typo3_src/vendor
• index.php is copied, because in my provider I need to do this.

TYPO3 9.5.9¶

• gridelements prevents start the Install Tool, so removing typo3conf/ext/gridelements
• Calling typo3/install.ph
• Updade wizard

• Create missing tables
• Add the default Extension Manager database tables
• Update backend user setting "startModule"
• Migrate pages.urltype to pages.url
• Migrate content from pages_language_overlay to pages
• Merge be_groups access rights from pages_language_overlay to pages
• Introduce URL parts ("slugs") to all existing pages
• Reminder to verify live system supports argon2i

• TYPO3 Backend
• Downloading and activating following extensions

• Gridelements
• powermail

• Calling typo3/install.ph
• Continue with Updade wizard

• Add the default Extension Manager database tables

• Running DB Analyzer

• Calling now the Frontend brings now the error.