[Monday December 11, 2023] john muhl via "Bug reports for GNU Emacs, the Swiss army knife of text editors" wrote:

> In Emacs 29.1 the image opens as expected:
>
>   emacs -Q
>   M-: (eww "https://www.gnu.org/software/emacs/images/emacs.png")
>
> On master it fails with "Wrong type argument: stringp, nil".
> Bisect says 4254544 is the first bad commit.

Recent changes in shr-put-image didn't account for the possible nil
value for ALT.  Attached patch fixes the issue on my end.