Hi. Stop creating empty categories by inserting translations.
Topic on User talk:HanV
You have created the empty category Category:Extensions_by_Miraheze/nl six times over the past two years, and each time I have deleted it.
Are you sure that the dutch category is empty? I am translating documentation that is partly translated. So if there is a category translated for 50% (just 2 messages) then i translate the missing message. It is possible that the category is empty, but it exists already. I also translate real documentation, not the category, so that there is maybe only one document in the category. It is not my purpose to create empty categorys.
The Dutch category is indeed empty.
Once you translate any of the extension pages belonging to the corresponding English category Category:Extensions_by_Miraheze, the Dutch category will no longer be empty. Once that's done, you can go ahead and translate the category.