[tex4ht] Bad interaction with bookmark.sty

[Michal Hoftich]

Dear Francis,

>To round off this issue, the author of dvipng has agreed to revise it 
>for the next release, presumably 1.18. The problem, if I understand it 
>correctly, is that the bookmark dvips driver, which is used by default, 
>inserts what is essentially an empty image, which dvipng does not 
>expect, and when trying to compute the resolution it divides by zero.  
>The bookmark dvips driver works as it does to avoid a clash with 
>another package; I think that was the recent change that upsets dvipng.
>

That's great! We can hope that they manage to pack the fixed version to 
TL 21.

Best regards,
Michal