# Use new cellgroup opener button for closing too?

Is there some way to keep the (new in v11.3) cell group opener button:

So I can use it to close the group?

Such a feature/hack would be nice as it takes me more effort to find the exact tiny vertical line to click on in the cell grouping outlines (on the right of the notebook).

• That was my immediate thought as soon as I saw this new feature. Of course when the group is open, the icon should change to a left-pointing chevron-like icon. Trying to find the correct cell bracket to close an open group was always harder and error prone than finding the bracket to open a closed group. – murray Apr 10 '18 at 14:04

Automatic closer is not there but it is on a todo list:

An inline closer is coming in the next version per popular request. The thinking was that it might be ugly/annoying to have closers everywhere, but the current plan is to only show closers on groups where you opened them with the openers. That plan may or may not survive the fire of testing.

Meanwhile you can create a custom one:

How to change the appearance of a Cell GroupOpener?

or use the old one, called "OutsideFrame" now:

ShowGroupOpener's mess in 11.3

• You can get at the function that attaches these via Block[{$Context = "FE"}, FrontEndResource["FEExpressions", "cellGroupOpenerInline"]] I've update the AttachedCell part of mathematica.stackexchange.com/a/133523/38205 to reflect what I saw there – b3m2a1 Apr 17 '18 at 8:37 • Using "OutsideFrame" in the OptionInspector/ShowGroupOpener I noticed that it only works for "SelectedNotebooks" but does not work when I choose "GlobalPreferences". I use Win7, 11.3 – Alexei Boulbitch Apr 17 '18 at 9:22 • @AlexeiBoulbitch Yes, that is exactly the problem in the question linked at the bottom. With Options Insector you switch a specific option. With preferences menu you change a labeled feature but it is not clear what is going on underneath. – Kuba Apr 17 '18 at 9:26 Here's a way to manually get a closer like the opener (seemingly does not work on Windows): attachGroupCloser = Block[{$Context = "FE"},
FrontEndResource["FEExpressions", "cellGroupOpenerInline"]] /.
{
Open -> Closed,
"CellGroupOpened" -> "CellGroupClosed"
};
FrontEndExecute@attachGroupCloser[NextCell[]];


There are surely ways to get this to bind at the stylesheet level, but it doesn't even matter as this is far from ready for primetime:

(note the excess whitespace)

Here's an explicit example:

CellPrint@
Cell[
CellGroupData[
{
Cell["Close me", "Subsubsection"],
Cell["goodbye cruel notebook", "Text"],
Cell["I'll disappear too!", "Text"]
}
]
];
FrontEndExecute@attachGroupCloser[NextCell[]];

• I'm not sure what to do to use it to enable a working 'closer'. – Kuba Apr 17 '18 at 8:53
• @Kuba does clicking on the box not work for you? Works for me. Of course binding at the style level will be rougher. – b3m2a1 Apr 17 '18 at 8:55
• No, it does not do anything when clicked in Win10 V11.3. Will try to take a closer look later. – Kuba Apr 17 '18 at 8:57
• @Kuba ahh another nice Mac vs Windows difference :) – b3m2a1 Apr 17 '18 at 8:58