On 01/08/2015 11:38 AM, Rob Wu wrote:
> The spec of the focusing algorithm [1] is not explicit about
> removed/hidden nodes. It seems to allow the change / blur / focusout
> events to be dispatched when an element becomes hidden or is removed
> from the document.
>
> All non-WebKit-based users agents (Trident, Gecko, Presto) do NOT
> follow this behavior. I.e. upon node removal, the change/blur/focusout
> events are not dispatched. WebKit and Blink deviate from the other UAs,
> they do trigger these events ( crbug.com/439484).
>
> This discrepancy became even more significant when Blink started to
> match other UA's behaviors and focus anchor elements upon click (
> crbug.com/388666#c10). Now, out of all browsers that focus an <a>
> element upon click, Blink is the only one that triggers the blur event
> when a node is hidden/removed. This difference has caused some broken
> websites and bug reports.
>
> There are two options here: - Dispatch change / blur / focusout when an
> element is unfocused, regardless of whether the element is still in the
> document. - Ignore hidden / removed elements in the focusing algorithm;
> i.e. do not dispatch these events.
>
> I'm inclined to vote for the second option, because the majority of
> the distinct user agents already follow this behavior. What do you
> think?
If by "hidden" you mean "an element styled with display:none", then
I think you're mistaken. I tested IE11, Chrome41, Firefox38 and Safari8,
and they all dispatch blur, although slightly differently. IE and Chrome
blurs directly at the style change (per spec); Firefox and Safari leaves
the element focused even after it's "display:none" but blurs it later when
a new element is focused. Not sending a blur event at all in this case,
as you suggest, would be incompatible with the existing behavior of all
four UAs.
I'm also seeing a different result than you in the case when the focused
node is removed from the document - both IE and Chrome dispatch a blur in
this case. It appears that IE suppresses the blur if the removal is done
inside the removed element's own 'onfocus' (as in your test).
I think the intention is that Firefox will change to be compatible with
other UAs and the spec[1] for node removal:
https://bugzilla.mozilla.org/show_bug.cgi?id=559561
(My tests are in that bug)
Personally, I think what the HTML spec says in this area makes sense and
since IE / Chrome is already compatible with it (mostly), I'd rather see
Firefox changed to match the spec.
/Mats
>
> Kind regards, Rob https://robwu.nl
>
> [1]
>
https://html.spec.whatwg.org/multipage/interaction.html#focus-fixup-rule-one
