Sorry I didn’t know the name for this “topic list”. 
But yes you’re right, it’s a toc.
And many thanks for the link! 
That is what I was looking for.
EDIT:
In the topic for the theme component I saw this screenshot.
So my question is, where can I found the plugin/theme component “Blur Spoiler”?
I have looked in the whole forum but I can’t find it.
EDIT2:
found it!