Important: The description of Categories names their rule 

Description 

The description below Categories of the project list content elements said that a main category selects all its subcategories with OR, and that several categories select with AND. Only the second part held.

The description now says what the lists do, in English and in German: a project is shown only when it carries every selected category, also where two of them are of the same category type. The subcategories of a selected category are not included.

Impact 

Only the text changed, the lists show the same projects as before. The label key flexform.categories.description is unchanged, so an override of it in a language file keeps its own text.

Affected Installations 

Every installation with a project list that has categories selected. A project that carries only a subcategory of a selected category is not listed. Give such a project the selected category as well.