Starting with TYPO3 12.4 this Guide was moved into TYPO3 Explained. See here: https://docs.typo3.org/m/typo3/reference-coreapi/main/en-us/Administration/Upgrade/Index.html
This document explains how to upgrade TYPO3 and migrate from Legacy to Composer mode.
| Repository: | https://github.com/TYPO3-Documentation/TYPO3CMS-Guide-Installation |
|---|---|
| Read online: | https://docs.typo3.org/m/typo3/guide-installation/main/en-us/ |