Sublime Text Handbook/WorkInProgress

Fold arrows – Supplementing the code folding support in the last beta, there are now buttons in the gutter to collapse text using the mouse. By default, the fold buttons will fade from view unless the mouse is over the gutter, however this is configurable using the fade_fold_buttons file setting. The fold buttons, and the space reserved for them in the gutter, can be removed with the fold_buttons file setting.