I created a sample content fragment from the simple template in the same way it has been mentioned in the documents.
I copied some text from one of my documents and added an image in between I also created a variation but I was unable to see actions drop-down for the master copy and also the summarize text was not there in the action drop-down for the variation.
Are there some restrictions or am I missing something.
Were you getting some errors?
I would request you to follow the below Helpx article:-
See this Helpx article:- Working with Adobe Experience Manager Content Fragments
I found the solution.
One needs to put the fragment inside a language folder so that the Language engine can be identified to process the text.