Feature request: Button to open/expand (or close/collapse) all directories

[minitauros]

Using Stackedit for a while I've actually managed to create quite a number of directories. Sometimes when I open Stackedit after not having used it for a while, all of the folders are all of a sudden closed again. I'm not sure what triggers this. But it makes it difficult to quickly find a file.

It would be amazing if there is a button for expanding/collapsing all directories at once.