Inconsistent Behavior in Pane Management

[jrk]

Changed Topic, See Update 2 Below

I am wondering if anyone can tell me if there is a way to configure the default position of the center splitter.

The default appears to be a 60/40 split and I would like to set this to a 72/28 split by default.

I can, of course, manually set the center splitter, but after a particular sequence of key presses the center splitter returns to the current default: 60/40.

Steps to Reproduce:

1. With all panes visible, move center slider to some position other than the default.
2. Ctrl+Shift+1
3. Ctrl+Alt+Shift+F12
4. Ctrl+Shift+1
5. Ctrl+Shift+1
6. Ctrl+Alt+Shift+F12

R Studio version: 1.3.959
OS: Windows 10

Update 1
This seems to be related to the following behavior:
If the center slider is between 0% and 40% from the left with all panes visible,
Ctrl+Alt+Shift+0 (Show All Panes) will reset the center splitter to 40%
If the center slider is between 60% and 100% from the left with all panes visible,
Ctrl+Alt+Shift+0 (Show All Panes) will reset the center splitter to 60%
If the center slider is between 40% and 60% from the left with all panes visible,
Ctrl+Alt+Shift+0 (Show All Panes) has no effect.

So, a simpler reprex is to set the center slider at 72% then

1. Ctrl+Alt+Shift+F12
2. Ctrl+Alt+Shift+0

Update 2
It appears this divide is hard-coded in the PaneManager.java file.
Ctrl+Alt+Shift+0 triggers a call to the function: layoutEndZoom which calls restoreLayout:

private void restoreLayout()
{
   // If we're currently zoomed, then use that to provide the previous
   // 'non-zoom' state.
   if (maximizedWindow_ != null)
      restoreSavedLayout();
   else
      restoreFourPaneLayout();
}

So it seems that zooming a column does not cause maximizedWindow_ to have a non-null value, thus instead of restoring the saved layout, it calls restoreFourPaneLayout, which then calls restoreTwoColumnLayout.

private void restoreFourPaneLayout()
{
   // Ensure that all windows are in the 'normal' state. This allows
   // hidden windows to display themselves, and so on. This also forces
   // widgets to size themselves vertically.
   for (LogicalWindow window : panes_)
      window.onWindowStateChange(new WindowStateChangeEvent(WindowState.NORMAL, true));
   restoreTwoColumnLayout();
}

private void restoreTwoColumnLayout()
{
   double rightWidth = panel_.getWidgetSize(right_);
   double panelWidth = panel_.getOffsetWidth();
   double minThreshold = (2.0 / 5.0) * panelWidth;
   double maxThreshold = (3.0 / 5.0) * panelWidth;

   if (rightWidth <= minThreshold)
      resizeHorizontally(rightWidth, minThreshold);
   else if (rightWidth >= maxThreshold)
      resizeHorizontally(rightWidth, maxThreshold);
   invalidateSavedLayoutState(true);
}

Which explains the behavior I saw above. Since these values are hard-coded, it's not going to be possible to change the default split.

Does this now become a bug report or a feature request for showing all panes from a zoomed left column to restore the saved layout?