bug#51716: 29.0.50; [PATCH] Expose xwidget navigation history to Lisp code

[Po Lu]

Eli Zaretskii <eliz@gnu.org> writes:

> Before I dive into the code, let me ask: why not use the usual Emacs
> history machinery for this?  IOW, have some xwidget-specific history
> variable that would store the browsing history, and use that variable
> in conjunction with foo-prev and foo-next commands?  Why do we need to
> reinvent the wheel for xwidgets, and why do that in C?

WebKit stores navigation history specially.  For instance, it implements
a feature where malicious (i.e. looping) redirects are not recorded in
history.  This is not available from Lisp, as the signals exposed by
WebKitGTK are insufficient to keep track of that data.  Further, I think
there is a way for web pages to tell WebKitGTK whether or not to record
themselves in history, which also cannot be implemented separately.

It can only be done from C, because the necessary information is only
available in C.