stuck Fontifying...

[John Stoffel]

Hi all,
I'm using emacs 26.1 on Debian Buster, running vm 8.2.0b and I've
suddenly run into a problem where if I try to view a certain email
(The rocket report from Arstechnica, early email before they post it
tomorrow) my VM instance get stuck saying "Fontifying..." and I can
only get out of it with C-g which is annoying.

I'm using VM from with in a Putty window, and I'm not using any fonts,
beyond being in UTF-8 mode.  But I *did* recently add a bunch of fonts
to my system because I was playing around with some LaTeX (boy, I'm
old school!! :-) documents that needed some Serif fonts installed.  So
I suspect emacs/vm is trying to use these.

I've tried setting (set font-log nil) and then trying to view the
message, but no log, there's no output in the buffer for:

   M-x font-show-log

And I don't have any font settings in my ~/.vm file either.
So I then tried running the profiler, and this is what I got, which
tells me that something in w3m is busted somewhere.  

- command-execute                                              882038  61%
 - call-interactively                                          882038  61%
  - funcall-interactively                                      881973  61%
   - vm-scroll-forward                                         881946  61%
    - vm-show-current-message                                  881946  61%
     - vm-decode-mime-message                                  881946  61%
      - vm-decode-mime-layout                                  881942  61%
       - vm-mime-display-internal-multipart/alternative             881942  61%
        - vm-mime-display-internal-show-multipart/alternative             
881942  61%
         - vm-decode-mime-layout                               881942  61%
          - vm-mime-display-internal-text/html                 881942  61%
           - vm-mime-display-internal-emacs-w3m-text/html             881914  
61%
            - w3m-region                                       881914  61%
             - w3m-fontify                                     881898  61%
              - w3m-fontify-anchors                            881895  61%
               - w3m-url-readable-string                       881887  61%
                - w3m-puny-decode-url                          775506  53%
                 - w3m-puny-decode                             462406  32%
                  - w3m-puny-decode1                           128674   8%
                   - error                                      44525   3%
                      apply                                     23604   1%
                    #<compiled 0xeedbfd>                         8996   0%
                 w3m-expand-url                                     4   0%


It's a shame it's not more robust.  Now to turn off w3m mode for a bit
and see how things go...

John