Need Help Finding a Package (indent vertical lines that collapses)


#1

Hi, in the photo below is indents vertical lines and a downward arrow when mouse hovers, could anyone tell me which package this is, thankyou.


#2

Do you mean settings > Show Indent Guide?


#3

The downward pointing arrows in the gutter are for code folding:

http://flight-manual.atom.io/using-atom/sections/folding/