Select input field in injected div doesn't work on parse.com in Firefox

Question

We have a Firefox extension that injects a div into the page. The div has a Z index of 2.14748e+9 (i.e. the highest allowed value). One site (parse.com) displays a modal Login dialog by putting a grey overlay over the whole page (absolute positioned).

Despite the fact that the z index of the overlay is lower (and so the div is not greyed out), the select field in the div does not open when clicked. If I right click on the field then the context menu appears, and after that it can be opened with a click as expected. So this looks to be some kind of focus issue.

All of this works fine in Chrome.

Update: Even when I delete the overlay div the input fields in the injected div fail to get keystrokes, so it looks like the modal dialog is capturing the events.

Answer 1

So it turns out the z-index of the injected div was causing the problem. Any value of 9999995 or greater (no really!) prevents it from gaining focus. Unless I'm missing something, this seems like a bug to me, so I filed it in Bugzilla.