bug#60308: 30.0.50; Can't read some PDF files any more

[Gregory Heytings]

> > > I can't read this file with emacs -Q:
> > >
> > > https://gnu.support/files/tmp/2023-01-05/FR%20205.pdf
> >
> > I can reproduce on Emacs 30 and Emacs 29, but not on Emacs 28
> >
> > Recipe: emacs -Q /path/to/the/linked/downloaded/pdf
> >
> > Observed: empty buffer
> > Expected: PDF page is displayed
>
> Can someone bisect this, please?

FTR, that file opens fine here, with Emacs 29 at ec172d748f, at 
d2a9dae400, at a6bad4d60f, at c59b8dfefa... and with Emacs 28.