In LaTeX, a short captions (that will appear in the List of Figures) can be made with the following code:
  \caption[Short caption.]{Long caption.}
With stargazer in R I tried this:
stargazer(mtcars, summary = FALSE, title="[Short caption]Long caption")
Which produces this output for the captions:
  \caption{[Short caption]Long caption} 
How can I make a short caption with stargazer?
                        
Using stargazer you can to disable it's float option. Nesting the stargazer chunk in a manually provided table environment then lets you customize any captions or labels manually, i.e.