Post-upgrade tasks for major TYPO3 Core updates

1. Flush TYPO3 and PHP Cache
2. Create missing tables and columns in the Database Analyzer
3. Run all Upgrade wizards
4. Change or remove columns and tables in the database analyzer
5. Flush TYPO3 and PHP Cache (again)
6. Reset backend user preferences (optional)
7. Update the language packs
8. Verify webserver configuration (.htaccess)