Hi Jens,

Updating EasyBlog will not erase post data. With that said, please backup the site files and database first before doing major updates to extensions or Joomla.

Should I do an new installation?

You can update EasyBlog by downloading the latest installer and install just like how you normally install extensions.

To be safe, I would suggest updating on a staging site first so that you are ok with the new changes/layout.