Error when migrating content from Typo3 4.5.15 to 12 composer

Hello Everyone,

I am new to Typo3. I want to migrate the content and the template from an old server (4.5.15) to a new Typo3 (v12) instance I created with composer.

I followed the documentation for importing things with composer. (link: Migration steps — TYPO3 Upgrade Guide main documentation).

  1. Exporting worked: I have a configuration .xml and a content backup .t3d
  2. Importing does not: It throws an error that I have not installed the: wt_twitter and the css_styled_content extensions, however, these extensions do not exist anymore.

I am unsure how to proceed

  1. Set Up a new template? Will this prevent importing the .t3d backup later?
  2. Adjust my .xml config?
  3. Manually rework the old packages?

Any advice, tips or approaches are appreciated!


Welcome to TYPO3!

The quickest thing is probably to set extensionDependencies to an empty array within the .t3d file or create empty extensions to represent wt_twitter and css_styled_content during the import.

The wt_twitter extension looks like it was abandoned many years ago, so you won’t be able to use it anymore.

css_styled_content was replaced by fluid_styled_content in TYPO3 v8.6.

PS! Even if you’re new, it sounds like the website you are upgrading is a few years old. 4.5.15 was released twelve years ago, so it’s great to hear your site is being upgraded! A lot has happened in the TYPO3 world over those years, so if upgrading directly proves difficult, try upgrading to some intermediary versions. It’s usually good to upgrade from version n to max n+2 in each step.

— Mathias