Krister,
Have you looked through this documentation? https://world.episerver.com/documentation/developer-guides/CMS/add-ons/customizing-the-tinymce-editor-v2/
There are several related subtopics under this topic.

Hi Bob

Thanks for your attention.

Yes I have read the documentation with subtopics several times :).

To me it seems these plugins does no longer exist.

The plugin is called: quickbars and then you can do something like this:

.AddPlugin("quickbars")
.Toolbar("undo redo cut copy paste removeformat");