2 <?xml-stylesheet href=
"chrome://global/skin/global.css"?>
3 <?xml-stylesheet href=
"chrome://devtools/skin/tooltips.css"?>
4 <window xmlns=
"http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
7 <hbox style=
"height: 10px">spacer
</hbox>
8 <hbox id=
"box1" style=
"height: 50px">test1
</hbox>
9 <hbox id=
"box2" style=
"height: 50px">test2
</hbox>
10 <hbox flex=
"1">MIDDLE
</hbox>
11 <hbox id=
"box3" style=
"height: 50px">test3
</hbox>
12 <hbox id=
"box4" style=
"height: 50px">test4
</hbox>
13 <hbox style=
"height: 10px">spacer
</hbox>