On Tue, Jul 26, 2016 at 4:34 PM, Alan Mackenzie <acm@muc.de> wrote:

M-: (setq debug-on-error nil) ; in buffer *scratch*, still.
M-: debug-on-error returns t.  How can this be?

​Good catch.  This problem has been there since at least 25.0.94 since I am running that and it exhibits it as well.

Bob