closed box should be automatically open when linked

[sorawee]

Say I have:

module type B =
sig
  include A
  (** @closed *)

  val x : t
  (** This is similar to {!y} *)
end

where y is in A.

Clicking the hyperlink y should open up the collapsed box automatically.

[panglesd]

For the records, I tested on firefox, opera and chromium, and only firefox has this problem: the details html elements are automatically opened on opera and chromium when linking to something inside them.

This could be achieved using javascript in firefox, but I wonder if we should do it or consider it as a responsibility of the browser...

[sorawee]

Thanks for testing! I should have checked other browsers too.

• Yes, this is considered a Firefox bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1820528
• A workaround was suggested in StackOverflow: https://stackoverflow.com/questions/37033406/automatically-open-details-element-on-id-call
• So yeah, as you said, we could do the workaround, or leave it as it is until Firefox fixes the issue. I'd be OK with either way.

[panglesd]

Related to this issue, there is also the "in page search" feature which should ideally open boxes. It does in chromium and opera but not in firefox (https://bugzilla.mozilla.org/show_bug.cgi?id=1724299). But this is much harder to do a workaround!

Thanks for finding the link to the bugzilla on this one! I spent too long trying to find it without success...

[Julow]

Considering that this is a browser bug is handy, as it avoid implementing a browser-specific workaround and shipping more javascript.
But I'm in favor of implementing a workaround as this might prevent users from reading documentation.

Could the following work in pure CSS ?

If a closed <details> contains a focused element, color it similarly to a focused element.
This would avoid hiding the focused element as the <details> element conceptually becomes the focused element while it's closed.