799413 - social sidebar has focus at startup

Status: RESOLVED WONTFIX

(Firefox Graveyard :: SocialAPI, defect)

Description

[Mark Hammond [:markh] [:mhammond]]

After starting FF when the sidebar has been previously enabled, the sidebar is focused, but the content window should have default focus.

Comment 1

[Mark Hammond [:markh] [:mhammond]]

It appears the problem is simply that the sidebar content is calling element.focus().  I doubt this is what we want to allow happening - in that case the element should be focussed *within* the sidebar, but shouldn't change which window actually gets focus.  Olli, do you have any thoughts?

Comment 2

[:Gavin Sharp [email: [e-mail]]]

Hmm, I would expect the code here to prevent that:
http://hg.mozilla.org/mozilla-central/annotate/90857937b601/dom/base/nsFocusManager.cpp#l1209

Since it prevents focus() in content from stealing focus from chrome (or from elements in other documents).

Comment 3

[Mark Hammond [:markh] [:mhammond]]

(In reply to :Gavin Sharp (use [e-mail] for email) from comment #2)
> Hmm, I would expect the code here to prevent that:
> http://hg.mozilla.org/mozilla-central/annotate/90857937b601/dom/base/
> nsFocusManager.cpp#l1209

And it does in the normal case :)  The focus stuff is hard to debug, so I'm a little vague about what is going on.  As content loads, it appears as though it doesn't yet have focus (the tabbrowser or app window does maybe?).  Then when content attempts to focus itself, it does get focus - at which point focus can't be stolen by other content.  It is that first grabbing of focus that we are hitting here.

Eg, if the content area contains the trivial HTML:

---
<script>
    window.addEventListener("load", function() {document.getElementById("theinput").focus()});
</script>
<input id="theinput">
---

The problem can't be reproduced - we can see the caret flashing in the input field.  When the sidebar loads and attempts to grab focus it fails (as expected).

If you comment out the load handler and try again, then the sidebar's attempt to get focus succeeds.  IOW, it appears neither the content window nor the sidebar initially has focus, so the first one to attempt to grab it wins.

Comment 4

[:Gavin Sharp [email: [e-mail]]]

Ah, tricky. Not sure how we can really work around that... short of disabling the sidebar from being able to "steal" focus (via .focus()) entirely, perhaps?

Comment 5

[Mark Hammond [:markh] [:mhammond]]

This will be hitting bug 604289 - but keeping this open to make sure it doesn't fall off the social radar.

Comment 6

[Shane Caraveo (:mixedpuppy)]

deprecation in fx51