Variable: image-auto-resize-on-window-resize
image-auto-resize-on-window-resize is a customizable variable defined
in image-mode.el.gz.
Value
1
Documentation
Non-nil to resize the image whenever the window's dimensions change.
This will always keep the image fit to the window.
When non-nil, the value should be a number of seconds to wait before
resizing according to the value specified in image-auto-resize.
This variable was added, or its default value changed, in Emacs 27.1.
Probably introduced at or before Emacs version 27.1.
Source Code
;; Defined in /usr/src/emacs/lisp/image-mode.el.gz
(defcustom image-auto-resize-on-window-resize 1
"Non-nil to resize the image whenever the window's dimensions change.
This will always keep the image fit to the window.
When non-nil, the value should be a number of seconds to wait before
resizing according to the value specified in `image-auto-resize'."
:type '(choice (const :tag "No auto-resize on window size change" nil)
(integer :tag "Wait for number of seconds before resize" 1))
:version "27.1"
:group 'image)