Buttons disappearing after upgrade from 7.0.0.rc1 -> 7.0.0

After upgrading from 7.0.0.rc1 to 7.0.0 I’m suddenly having a problem where my custom buttons are disappearing.

I’m not sure where to start with debugging this, so I thought I’d show what’s happening here first.

From inspection with Firebut, the problem apparently stems from a
visibility: hidden
setting in the
style
attribute of a [font=Courier New]

[/font] element containing the buttons. This is best shown with two screenshots from Firebug.

The first screenshot is what 7.0.0 produces. Notice: no buttons visible. The second is the same thing with the
visibility: hidden
setting disabled manually in Firebug, which then allows the buttons to be seen.

These buttons live inside a
GridLayout
.

Any ideas??
12772.png
12773.png


Ticke #10947
filed with reproducible test case.