No "additional button" in the visual editor

“add a shortcode using the additional button provided in the visual editor”

I installed the plugin, copied a sample short-code into one of my page, works nicely. But I can’t find any button related to this plugin in the visual editor. Am I doing something wrong?

It would be also great to have a ‘template short-code with all the possible parameters – for newbies like me.

Many hanks in advance, Janos

https://ww.wp.xz.cn/plugins/wp-category-tag-could/