Fold Lines
Display full-width fold lines, similar to Notepad++ or Komodo editors.
The solution is rather simple, really: It adds a "folded" class to the editor, similar to how the line number is marked. Therefore, to modify the style of the line marker, you could do something like this in your styles.less file:
atom-text-editor.editor .line.folded {
border-bottom: 1px dashed salmon; // Mmm.. salmon..
}
To remove underline from the line number marker:
atom-text-editor.editor .line-number.folded {
border-bottom: none;
}
To hide default fold marker (which I feel to be redundant while fold lines are visible):
atom-text-editor.editor .fold-marker {
display: none;
}