Is that block by chance part of a Stack or copied from another page? I have see it where if it is one of those things it behaves this way (same with the core form block).

Dear Hutman,
The topic block on the blog page is just a block but the topic block on the page where the post is, that is indeed a part of a stack (so it is made by the C5DK makers).
Actually nothing is copied from another page but just right away installed according the instructions the maker of the C5DK Blog add-on is advising me. And according them the add on is always working ... but tja not on my site

The C5DK Blog add-on maker told me perhaps it is an sub domain issue, but I had already a blog running in another theme without problems ...

Slowly I become so tired of all this .... Invested in themes, add-ons, lots of hours and months to get something running and every time there is something what is not working ...

Perhaps some one else here can help me ?

Thanks anyway for your ideas.

I see in your list of posts that you have a post called "Topic". It appears that the addon uses the word topic in the filter URLs. If you delete that post does it solve the issue?

JA
You are the best
It solved the problem
Now I can sleep good

Thank you so much :-)

Now just another thing

When I chose the different topics , the screen is moving by one topic choice to the left ...
How is that possible ??

Gr Stefan