Hello All,
I can't see any operation links in context, node and Appearance overview.
see next screenshots
Screenshot 01
Screenshot 02
Screenshot 03
Does anyone have an idea how this could get.
Or where the error is


Odd. Do you have full permissions set for the user as whom you have logged in? Just being an admin user (other than the original admin user) does not give permissions automatically, they have to be set.

If there is really a bug there may be a clue at Reports > Latest Log Messages.

There were no errors in the logs and I use de main Admin account.

I would look also at php / apache logs.

After that your options for debugging are just to disable all non-core plugins and themes, and (assuming it works) re-enable one by one; and / or look at the site with Devel module enabled and its show query log enabled, and try to trace the problem. Also might be worth trying the site on a different server / laptop.

Thank you all for the comments.
There was a conflict with the custom breadcrumb module.
I found this all weird. Because this is a commonly used module.
But I had version 7.x-2.0-alpha3.
With version 7.x-2.x-dev is everything ok.