Black-Studio TinyMCE widget not showing up in visual editor

Black-Studio TinyMCE widget not showing up in visual editor I have to work on the widget a long time ago and worked so it worked great but today it does not work anymore. There is no content that I have worked at that time. But the content is there – I see it only if I mark it all.

MyWebsite
Here is the content on my site, which I worked with the Black Studio TinyMCE widget.

But today I can not rework it.

What could be the problem?

Thank you!

Regards
Conrad I.