If in OptionInspector I select option "Inline" for Cell Options > Display Options > ShowGroupOpener for section-like cells, then when such a group is closed it shows an icon that is a little box, with rounded corners, containing a symbol similar to a right-pointing chevron, like this:
And when the group is open, the icon changes to one where the chevron points downward, like this:
(Ignore the color there: that's an artifact of a particular stylesheet I'm using.)
I want to be able to explain those icons in a Text cell. How can I insert those symbols there?
The best I've been able to obtain so far is the following:
openerClosedIcon = Framed[ Style["\[VeryThinSpace]\[VeryThinSpace]\[VeryThinSpace]»\ \[VeryThinSpace]\[VeryThinSpace]", Bold, 24], FrameMargins -> None, RoundingRadius -> 5]
openerOpenIcon = Rotate[openerClosedIcon, -90 Degree]