Errors with help(...) "failed to translate HTML"

General
1

I installed SWI Prolog with homebrew on my Mac. I run it with swipl in the terminal app. Certain help commands only seem to work once. For example:

% swipl
Welcome to SWI-Prolog (threaded, 64 bits, version 9.0.4)
SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software.
Please run ?- license. for legal details.

For online help and background, visit https://www.swi-prolog.org
For built-in help, use ?- help(Topic). or ?- apropos(Word).

?- help(append).
[shows documentation for `append`]
q [goes back to prompt]
?- help(append).
ERROR: Failed to translate to HTML: \man_pages([append/1,append/2,append/3,append/4],[no_manual(fail),links(false),link_source(false),navtree(false),server(false)])

Is it a bug?

2

Yes. It is was very recently discussed here and fixed in the sources currently available on the git repo.

Typically, the best place for the docs is the website. The search box provides look-ahead, then select the hit you are interested in.