New option for making Gnus window layouts atomic

* lisp/gnus/gnus-win.el (gnus-use-atomic-windows): New boolean
  customization option.
  (gnus-configure-windows): When removing old window layouts, check
  for and remove atomicity.
  (gnus-configure-windows): When gnus-use-atomic-windows is non-nil,
  make Gnus window layouts atomic.
* doc/misc/gnus.texi (Window Layout): Document.

1 files changed, 8 insertions, 0 deletions

diff --git a/doc/misc/gnus.texi b/doc/misc/gnus.texi
index fb9581f9853..d535c1a49ef 100644
--- a/doc/misc/gnus.texi
+++ b/doc/misc/gnus.texi
@@ -22923,6 +22923,14 @@ window is displayed vertically next to another window, you may also want
 to fiddle with @code{gnus-tree-minimize-window} to avoid having the
 windows resized.
 
+Lastly, it's possible to make Gnus window layouts ``atomic''
+(@xref{Atomic Windows, , Atomic Windows, elisp, The GNU Emacs Lisp
+Reference Manual}) by setting @code{gnus-use-atomic-windows} to
+@code{t}.  This will ensure that pop-up buffers (e.g. help or
+completion buffers), will appear below or to the side of the entire
+Gnus window layout and not, for example, squashed between the summary
+and article buffers.
+
 @subsection Window Configuration Names
 
 Here's a list of most of the currently known window configurations,