Start Emacs and visit a PNG or JPG etc, file. For example foo-01.png.
It is displayed correctly and fitted to the windows *width*. Now do
the same with another graphical file. For example foo-02.png. It also
is displayed correctly and fitted to the window WIDTH.
Close foo-02.png and for foo-01.png click Image - Fit to Window
Height. It complains with a BELL sound and with the message:
Assertion failed: (= (cdr size) (- (nth 3 (window-inside-pixel-edges))
(nth 1 (window-inside-pixel-edges)))), 821, 814
user-error: Minibuffer window is not active
but the file is displayed correctly, at least in appearance! If now
one re-visit foo-02.png it is visited in Fundamental mode and with the
message:
Cannot display image: ((= (cdr size) (- (nth 3
(window-inside-pixel-edges)) (nth 1 (window-inside-pixel-edges))))
821 814)
It seems that this build of Emacs does not like "Image - Fit to Window
Height". The graphical format (PNJ, JPG..) seems irrelevant..